عنوان مقاله [English]
Low efficiency of water use in agricultural sector, make in nessesery to do strategies for optimization of cropping pattern and therefore water consumption, especially in dried areas such as Khorasan Razavi province. Principal selecting of these strategies needs that the results may be evaluated using relevant simulation models. Saffron can be the right product in terms of water saving. The aim of this study is to investigate the effects of saffron area expansion on the allocation of water resources and increase the income of farmers through the use of a model based on an extended Positive Mathematical Programming model that includes the possibility of future develop in cropping patterns, along with water allocation through a production function based on the amount of irrigation water. Required data are collected from 200 questionnaires completed by saffron producers in Torbat-e Heydarieh and Zaveh counties in year 2014. The data collected was analyzed using the software GAMS and imposing different senarios on three group of small, medium and large farms. Results of the increase in saffron cultivation shows change in cropping patterns from higher water demand products towards saffron. Positive results of this policy are increase in net income and decreasing water consumption in all three type of farms. Results of increase in available water resources that allow farmers to exploit part of the dedicated land to the cultivation of saffron, do not show uniformity results for different groups of farms. This implies that, in addition to pricing, other strategies such as investing in new technologies to improve water use and water resource management may improve economic statement and agricultural development, especially on small farms of this area.