Evaluation of geostatistical methods for estimating electrical conductivity and pH of stream drained water in Hamedan-Bahar Plain

In this research, the spatial distribution of electrical conductivity and pH of springs, ghanats and the base flow concentration places on the streams of central and south-west and central parts of the Hamedan-Bahar plain were evaluated. using different geostatistical methods such as Kriging, Minimum Curvature, Inverse Distance, Natural Neighbor, Local Polynomial and Radial Basis Functions, 108 water samples of different sites of the plain’s hydrographical network were sampled during July 2005 and EC and pH values were measured for each sample. The performance criteria for evaluating the used methods were Root Mean Square Error and General Standard Deviation along with the Cross Validation method. The results showed that Local Polynomial and Inverse Distance were the best methods to estimate EC and pH, respectively. Radial Basis Functions were also found as the most unsuitable method for estimating EC and pH.