Comparison of water permits trading policy among cotton farmers in Golestan

In this study, due to comparison of water permits trading and non-trading policies, two water allocation programs among cotton cultivators based on Interval-Parameter Two-Stage Stochastic Program model was designed. Then the results of two policies were compared together based on surplus water volume index, reduction in water deficiency and the area of irrigated land. For this study, 20 farm lands of cotton in Ghasemabad-village were selected which irrigated by released water from Voshmgir dam located in Aq-Qala city. The comparing of the results showed that water allocation under permit trading of cotton farmers led to water saving with low and high bounds of [47.36 , 52.89] ×103 m3 and decreasing in water deficiency equals to the interval of[35.54 , 42.66]×103m3and with decreasing in land use equals to bounds of [6.4 , 7]ha than non-trading policy ,so that the value of the total profit of the cotton cultivation system is maintained under trading policy equals to the interval of [56.82 , 94.29] million toman. Generally, trading policy than non-trading can lead to more effective allocation in view of water saving and reduction in water deficiency, but this policy can also reduce cotton irrigated area and in long term is resulted to remove of some farmers from agricultural activities.