—The goal of this research is investigating variation in the water content due to change in the groundwater level and climate change using the optimization methods in different soil layers. Decrease in the precipitation rate in recent years has resulted in the overuse of groundwater, lowering the groundwater level and change in the soil moisture conditions. The result of these changes is considerable subsidence in the soil layers, where its accurate calculation and estimation requires precise knowledge of the soil conditions especially the water content at the soil surface and in deep layers. In this study, the performance of two optimization methods in estimating of the soil moisture profile is investigated: modeling by the inverse method and the artificial neural network and this problem is solved using the field data presented in the literature for a one-year study period. For this purpose, first, the field data corresponding to an interval of two months was utilized to determine the required parameters for each of these models. Then using the obtained data, the soil moisture profile at different soil layers and for the remained studied interval was estimated and compared to the observed data. Based on the obtained results, in the case of accurate estimation of the model parameters, utilizing the optimization methods would greatly reduce the cost and time associated with investigating the problem and at the same time would provide an acceptable prediction of changes in the soil moisture conditions. Also, the inverse method, considering the soil hydraulic parameters, would provide a better approximation of climate change at different times.
—Optimization methods, soil moisture profile, effective hydraulic parameters, unsaturated soil.
S. Farid F. Mojtahedi is with the Department of Civil Engineering, Sharif University of Technology, Tehran, Iran (e-mail: Farid_Fazel_M@Yahoo.com).
Mohsen Sadoughi is with the Department of Civil Engineering, Islamic Azad University, Ardabil Branch, Iran (e-mail:Mohsen.email@example.com).
Cite: S. Farid F. Mojtahedi and Mohsen Sadoughi, "Estimation of Soil Moisture Profile Using Optimization Methods," International Journal of Modeling and Optimization vol. 7, no. 1, pp. 54-59, 2017.