Geostatistic Approaches for Investigating of Soil Hydraulic Conductivity in Shahrekord Plain, Iran

Soil hydraulic conductivity is the most important physical parameter that impresses drainage projects from technical perspective. The purpose of this study is the investigation of spatial changes of hydraulic conductivity, calibration, and feasibility of using various methods of geostatistic in Shahrekord Plain in the West of Iran. Hence Kriging (K), Inverse Distance Weighting method (IDW), Local Polynomial Interpolation (LPI) and Global Polynomial Interpolation (GPI) methods were used for interpolation. For evaluation these methods we used Cross-Validation Technique with MAE and MBE statistical criteria. Studies showed that spatial correlation of hydraulic conductivity in this region is weak and kriging was recognized as suitable method (C0/Sill = 81%). Ordinary kriging method contains the lowest rate of MAE and MBE. In fact, the high flexibility of this method than the other methods studied shows the high accuracy of this method because of having variety models and parameters. Also results showed that ordinary kriging with a circular model are the most suitable method for interpolation in zoning the hydraulic conductivity because of lower errors and relative deviation.