COMPARATIVE BETWEEN GEOSTATISTICAL MODELS WHICH APPLIED TO ANALYSE THE MAJOR ANIONS CONCENTRATION IN GROUNDWATER KARAPINAR, KONYA, TURKEY*

Groundwater is one of the most significant resources in arid and semi-arid areas and is essential for drinking, irrigation and industrialization. Land use classification map used based on 0.5 km MODIS-based Global Land Cover Climatology, GIS application are important tool that had been used for estimating and predicting the quality of groundwater. Samples were collected from 30 wells in summer and 20 wells in winter within the study, in addition to many wells out the study area to obtain best analysis of anions for year 2013 , the objective of this study is for predicting the spatial distribution of major anions concentration in groundwater of Karapinar in Konya city such as SO42-, Cl-, NO3-, HCO3- and PO43- for assessing accuracy of various geostatistical wizard techniques like CoKriging, RFB and IDW, the map of anions concentration in groundwater was prepared for two seasons utilizing geostatistical models (Ordinary Kriging (OK), Simple Kriging (SK), Universal Kriging (UK), Inverse Distance Weighting (IDW) and Radial Basis Functions (RBF) methods ) existing in the geographic information system (GIS) and compared between these methods then choosing the best model for observed the spatial distribution of pollutants, the optimum model was used to predict anions concentration in Karapinar. Where the best model of each anion has been chosen based on prediction errors, and on the relation between measured and predicted concentration for each anion. All the anions groundwater parameters were evaluated and compared with WHO 2008 Standards, some of the collected groundwater samples present the investigated parameter levels exceeded the permissible limits of WHO 2008. Therefore, most groundwater samples are considered unsuitable for drinking and irrigation due to its high salt content based on anions concentrations in this study and land use classification map that including Croplands (yellow), Grasslands (green), Barren or Sparsely Vegetated (Grey), Urban and Built-Up (red) and Open Scrublands (Chartreuse).