Evaluating the effect of different water resources management scenarios with the approach of meeting environmental water requirements of the wetland at the catchment (Case study: Amirkalayeh wetland)

The scarcity of available water resources, on the one hand, and the increase in water demand, on the other, have upset the balance between water supply and water demand systems. Consequently, it is necessary to prevent the destruction of this valuable ecosystem and its adverse effects by considering the principles of the integrated water resources management program, determining the environmental status of wetlands such as Amirkalayeh wetland, and improving its water resources management. The main purpose of this study was to investigate different allocation scenarios for the provision of wetland ecosystems based on the principles of integrated water resources management. To aim this purpose, the water resources system of the wetland and its catchment area were simulated with the WEAP model. First, the model was calibrated for the current condition of the wetland in the reference scenario at the water years 2011-2020 whith R2 and RMSE statistical indices of 0.99 and 0.1 for the wetland volume and 0.95 and 0.3 for the creek discharge, respectively. Therefore, water shortage values were estimated to achieve the minimum and optimal ecological conditions of the wetland. Then, the effect of the management strategies on the balance of water resources of the wetland was investigated by compiling different management scenarios. The results showed that the implementation of scenarios at the wetland scale and its catchment would increase the volume of water in the wetland between 0.5 to 4 and 0.3 to 1.7 million cubic meters, respectively. Furthermore, simultaneously implementing scenarios of increasing the volume of the wetland’s reservoir could provide the wetland's water requirements by constructing a levee, increasing irrigation efficiency, and eliminating the occupation of agricultural lands in the wetland bed and its margins. Also, when agricultural water requirement is provided, the water requirements of the wetland will be met so, even at a higher level.