The optimal cropping pattern for Sistan water resources management was determined through a goal programming technique within the GAMS programming environment . Results showed that the optimum cultivation area and net profit of the agricultural sector in the Sistan region could increase up to 18.1 and 39.8 % , respectively,compared to the current status. An increase in the farm irrigation efficiency from the current 35 to 55 % would increase the net profit of the agricultural sector by 49.7% despite 6.4% reduction in water consumption. At the same time, 20% increase in the efficiency of water delivery system to farmlands would lead to 8.2 and 17.2% increases in the cultivation area and net profit, respectively. The results of combining these two management scenarios indicated that farming net profit would increase by 64.3%, while total water consumption in agricultural sector would decrease by 2.3%. Under wet condition , cultivated area and net profit would respectively increase about 32 and 44%. However, upon drought ears , the cultivated area and net profit would experience 86.9 and 87.3% loss, respectively.

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