Determination of optimal crop pattern to prevent the water table drawdown using PSO algorithm

Nayshabour aquifer in Khorasan Razavi with arid and semi-arid climate, have an important role in agricultural production by using groundwater resources. In this study, the required equations for estimating water table variations are obtained using the groundwater balance model. Since there are too many variables in the objective function of water consumption, in this study, PSO optimization algorithm (Particle Swarm Optimization), a Meta heuristic method which requires less computation and is more efficient, was used to determine the optimized crop pattern and intensification. Model results based on a normal year (2008) showed that in order to minimize the drawdown in the water table, with rainfall equal to average annual rainfall of the region, farmers only permitted to exploit 359 million cubic meters from the Nishabour aquifer that this water volume can irrigate only 59 706 hectares that it is 48,789 hectares less than the current status. So that 48802 hectares of cropping land reduced and only 183 hectares of land were added for planting tomatoes.