Estimation of minimum ecological water level of ‎GooriGol wetland using a multi-objective programming model

Estimation of the ecological level of water bodies is critical to protect aquatic ecosystems and has become a major issue in sustainable water resources planning. In recent decades, several methods are utilized to estimate the minimum ecological flow in rivers and the minimum ecological level in lakes and wetlands. In this research, a multi-objective programming model, which is a comprehensive ecological level or environmental flow estimator model, has been used to determine the ecological level of the GooriGol wetland. The model has two objective targets with two indices of water and ecosystem indicators. The level of water in the wetland has been selected as a water index and three species of important ducks in the wetland have been chosen as the ecosystem indices. The first objective function is to minimize the water index, while the second objective function is to maximize the ecosystem indices, so that more habitats are provided for aquatic ecosystems. Therefore, the aim of this model is to provide conditions for the largest ecological operations with the least amount of water. In order to solve the multi-objective optimization model, the sum of weighting technique is used. The computational results indicated that the minimum ecological level of the GooriGol wetland is 1912.6 meter. The field observations during the recent decade are in agreement with the obtained result of this research and indicates the decreasing the water level from 1912.6 m causes considerable declining in the ecological performance of the wetland.