Using System Dynamics for Simulating Subsurface Drainage Systems in Clay Soils

Abstract

The system dynamics technique is used as a decision tool for engineering problems. It is one of the object oriented approaches that study and manage complex feedback systems. In this paper, the system dynamics technique was used to simulate the performance of a drainage system under wheat crop in a clay soil. The model was calibrated and validated using observed experimental field data (drainage discharge and water table level) collected from Mashtul Pilot Area (MPA), Egypt. The results indicated that, the model is capable to predict hydrological parameters such as water table fluctuation, drainage discharge, upward flux, evapotranspiration, deep percolation, infiltration, runoff, soil moister content and unsaturated hydraulic conductivity on the basis of variation of soil moister content. The trends of the parameters found to be legible. Six statistical indexes were calculated to determine the agreement between the observed and simulated values of water table and drainage discharge. Results indicated that the system dynamics technique can be considered as a good decision tool to predict the subsurface drainage water precisely.