Optimizing Exploitation Pattern of Water Resources in Order to Maximize the Social Benefits in Fars Province

Development or limitation of agricultural crops planting in different regions should be with respect to the production possibilities and water resources limitation and this emerges need to design a comprehensive model of the cropping pattern. The results showed that crops such as wheat، corn، tomato، onion، watermelon، melon، cucumber and vegetables have comparative advantage however; barley and cotton not have comparative advantage. Nominal protection coefficient for all agricultural crops in Fasa city is calculated less than one and also، the nominal protection coefficient of the inputs indicating make subsidized all inputs are indirectly. Also، the effective protection coefficient for all products of this city is less than one. The results of determining the optimal cropping pattern to goal of maximize the social benefits showed that acreage has decreased which amount 537. 37 acres relative to the optimal cropping pattern to goal of maximize private benefits. Furthermore، the results showed that social benefits and gross margin of application of the models for different purposes (maximize the social benefits and maximize private benefits) maximize social benefits and private profits in Fasa city are equal to 782517004014 and 191495971166. 27 tomans respectively. In this regard، although Social benefits in maximization model of social benefits is more than social benefits in maximization model of gross margin but gross margin in maximization model of gross margin is more than gross margin in maximization model of social benefits. As a result of this study show that although، the Fasa city in producing agricultural crops such as wheat، corn، tomato، onion، watermelon، melon، cucumber and vegetables have comparative advantage but، in order to maximize the social benefits derived from the exploitation of available water resources (with respect to the real value of water in the model due to lack of water resources) in the agricultural crops group that have comparative advantage، production of crops that require less water is permissible.