Evaluation and comparison of Multilevel Optimization Method and IPARM model to Estimate Furrow Irrigation Infiltration Parameters

The parameters of infiltration equations have a key role to evaluate and design irrigation systems and it is essential to estimate them with high accuracy for increasing irrigation efficiency. In the present study، two approaches consisting multilevel optimization method using advance، recession and runoff data and the IPARM model using advance and runoff data were compared for estimating infiltration parameters of furrow irrigation. The field study in order to collect required data was conducted in Karaj in 2014. Fourteen irrigation events with two inflow discharges (0. 29 and 0. 44 L/s) during maize growing season were carried out. Based on estimated infiltration parameters of the Lewis- Kostiakov equation، the mean relative error of the IPARM and multilevel optimization methods were obtained 8. 1 and 8. 5 percents، respectively، to estimate total infiltrated volume. The results indicated that both methods underestimated the total infiltrated volumes for all datasets. The IPARM method had less error than the multi-level optimization method. However، both methods had satisfactory performance to estimate infiltration parameters in furrow irrigation.