Determine optimal crop pattern with an emphasis on increasing the irrigation efficiency in lands of Mollasadra Dam in Fars province

The aims of current study are maximization of annual gross margin and allocation of surface water and groundwater in farms under Mollasadra dam; containing Kamfiruz and Korbal plains. For this purpose, deterministic linear programming (DLP) and chanced constrained linear programming (CCLP) to representation an optimal cropping pattern with uncertainty were used. To investigate the effect of increasing irrigation efficiency on annual gross margin, four irrigation efficiency hypothetical scenarios include 50, 60, 70 and 80 percent in certainty and uncertainty conditions (in three levels of 90, 95 and 99 confidence percent) were used. Main crops of the study area, in the form of dry and irrigated agriculture and for the spring (dry) and fall (rainy), were considered. Required data for cultivated area and the type of crops has been derived from database of Fars Agriculture Jahad Organization in 2013, and requirment data for amount of rainfall, surface water and groundwater has been derived from Fars regional water Organization in 2006 to 2013. The results indicated that by applying long run planning for a 30 percent increase in farm irrigation efficiency, annual gross margin of farmers increases from 390 billion Rials to 602 billion Rials and 1 million cubic meters groundwater would be saved. Therefore, a research about water saving technologies and investment in new irrigation systems, which leads to improvement of irrigation efficiency, is recommended.