چكيده به لاتين
The main purpose of this research is to develop a model to simulate the mechanism and operation of an informal water market and validate it based on real data from the region. This model has been developed by using an agent-based method in the NetLogo software environment. Due to the many similarities between the water market in the region of Mojen and an informal market, this water market was selected as the case study of the present study. The importance of social interactions in modeling the informal water market in comparison with the formal market led to the development of a model for simulating a social network between stakeholders, taking into account the interactions in the region. In all steps of modeling this market, there has been an attempt to design process of scenario and model, according to the details of the area by the in-person presence in the region, conducting field research, visiting agricultural lands and orchards, as well as interviewing with farmers along with filling in questionnaires. Validation of agent-based models often faces challenges due to the lack of available information. These challenges are also considered in previous agent-based models of water markets. The validation of prices in temporary water trades in the market as well as the area under cultivation in the region are calculated as micro- and macro-validation of the model. These validations were done by using the Nash-Sutcliffe method, based on observations in the area and data obtained from the model. This criterion for the mentioned validations was 0.78 and 0.83, respectively. Since modeling involves simulating social networks, these numbers indicate the reliability of the developed model. Calibration of the developed model has been done by BehaviorSearch tools, which can be coupled with NetLogo software, as well as the Solver tool, which is in Excel. Furthermore, by the development of this model, some studies about the effects of the water market on the region have been done. According to these studies, it was concluded that due to the existence of a water market in the region, the average number of people who have not been able to meet their water needs for irrigation has decreased from 88 to 55 annually. Market performance in preventing declining under cultivated area in low rainfall years has also been considered. For instance, in the years 2006 to 2008, which there was a severe reduction in rainfall, the reduction of cultivation has been small. A comparison of the performance of the informal water market in the region with a hypothetical formal market showed that an informal market can have almost 80% of the formal market performance. Also, in this study, the role of farmers’s interactions in water trades was investigated, and it was concluded that increasing the number of interactions in the region has a significant effect on increasing water trades. Market interactions are so important and vital that by increasing these interactions, the average number of farmers below the poverty line can be reduced by up to 25%.
