Application of the Socio-Hydrology Approach for Evaluating the Impacts of Farmers’ Activities on Surface and Groundwater Resources in Climate Change Condition (Case Study: Mahabad Plain, Urmia Lake Basin)

In this research, a new framework of socio-hydrological modeling framework has been developed in order to evaluate the performance of human-water systems. For this purpose, a comprehensive hydrological model has been developed by combining SWAT and MODFLOW models to simulate surface and underground water resources. Then by using Value-Belief-Norm Theory, the effective factors in the water consumption behavior of farmers are identified. Finally, by combining the SWAT-MODFLOW model and the Agent-Based Model based on the theory of VBN, the behavioral pattern of farmers in choosing the type of cultivation and irrigation method has been evaluated. The theoretical framework of the VBN theory and the behavioral rules of agents in ABM are designed based on the data collected from Mahabad plain farmers through field questionnaires. Afterward, an analysis and investigation were conducted on the response of the socio-hydrology model that was developed, utilizing climate change data from the 6th IPCC report and the ACCESS-CM2 model, for the planning horizon. The results showed that those farmers who are below the poverty threshold try to improve their unfavorable economic situation by choosing profitable crops for farming. Therefore, if no fundamental change is made in management policies in the future, the climate change will reduce the profit within the agricultural sector and the pattern of cultivation will change towards crops with high profits and yet high water consumptions. If the management methods remain unchanged in the future, the yield of the crops, the income of the farmers in the region, and at the same time the inflow to Lake Urmia from the Mahabad River will decrease significantly. Therefore, it is recommended to adjust the management policies as a way to deal with the effects of the climate change. In general, the results of the present research can be considered for future planning and policies and for estimating how changes in economic and psychological factors for farmers affect the restoration of Lake Urmia.