Abstract
Using system dynamics (SD) approach, this paper develops a simulation model to study the behaviors and relationships
within the agricultural system at national level and analysis the future scenarios. The proposed model considers three major
sub-systems: demand side (population and income), supply side (land use, water resources, and productivity), and regulatory
side (barriers, incentives, and support). Iranian agricultural system is modeled using this approach and the future conditions
are simulated under three if-then scenarios up to 2040. The results show that under the policies as current conditions, the
demand for the agricultural products will rapidly increase due to the population growth and economic development. However, agricultural land use and domestic supply does not experience much growth because of crucial limitations in the
climatic conditions, available water resources, and rather low productivity; therefore, the gap will be compensated through an
ever increasing import. The suggested SD model helps policy makers to identify the bottleneck points in the system based on
simulation results and then, improvement policies can be made according to these bottlenecks. Some improvement policies
for supply side have been proposed and effectiveness of them on increase in production and agricultural land use
development has been demonstrated. By improving supply side policies alone, the Iranian government’s goal of agricultural
self-sufficiency is not likely to be achieved and it is essential to improve the demand side policies in this regard. The
suggested model has proven to be useful for Iranian agricultural system, and its methodology could be used as a decision
support tool for land use planning, policy making and managements of agricultural sector.
