optimization model

Modeling socio-hydrological interactions are one of the essential requirements for water resources management in water-stressed areas. The Ardabil aquifer (Northwestern Iran) is one of the restricted aquifers under intense development activities. The water table is dramatically declining and leading the area to an environmental disaster. In this study, a simulation-optimization model has been developed for solving the Ardabil groundwater problem, which simulates groundwater level changes and determines the optimal water exploitation values. These models have been linked by a new method in the MATLAB which provides access to various MODFLOW packages and takes up less memory. The simulation-optimization model has been then linked to an agent-based model, which simulates agents’ behavior and their interactions. For this purpose, firstly the key agents and their desirability have been determined. Then, the particle swarm optimization algorithm is used to estimate the agents’ desired groundwater exploitation values. In the next step, the best solution using the compromised programming method is selected according to the experts' point of view. Finally, the agent-based model provided the final exploitation values, taking into account social pressure and management rules (incentive and penalties). The results show that groundwater demand is reduced up to 22% in comparison to the initial value. This demand reduction resulted in 90 cm of the increase in the groundwater level for the entire plain.

Groundwater in coastal areas is an essential source of freshwater that warrants protection from seawater intrusion as a priority based on an optimal management plan. Proper optimal management strategies can be developed using a variety of decision-making models. The present study aims to investigate the impacts of environmental changes on groundwater resources. For this purpose, a combined simulation-optimization model is employed that incorporates the SUTRA numerical model and the evolutionaty method of ant colony optimization. The fresh groundwater lens in Kish Island is used as a case study and different scenarios are considered for the likely enviromental changes. Results indicate that while variations in recharge rate form an important factor in the fresh groundwater lens, land-surface inundation due to rises in seawater level, especially in low-lying lands, is the major factor affecting the lens. Furthermore, impacts of environmental changes when effected into the Kish Island aquifer optimization management plan have led to a reduction of more than 20% in the allowable water extraction, indicating the high sensitivity of groundwater resources management plans in small islands to such variations.

Qazvin’s traditional gardens have had important roles in the history of Qazvin. But today because of two major problems, water shortage and city expansion, these gardens are in an improper situation. In this paper using the Operational Research method, it is tried to develop a management inclusive plan with two fundamental policies: gardens vitalize in a short-term horizon and gardens flourish in a long- term horizon. The action plans are determined for the policy makers in order to achieve sustainable development in the garden complex. According to the results of this study, in the framework of policies mentioned, water distribution andrelated expenses over the gardens would be fair. Also the irrigation efficiency in the garden complex would be improved from 33% in current situation to 38% in short-term horizon and 59% in long-term horizon.