Investigation of three Kriging models performance for assessment of the most important groundwater qualitative variables(Case study: Bam plain)

Overpopulation and consequently excessive exploitation of groundwater resources, not only has reduced thequantity of groundwater resources but also has degraded the quality of these resources. The study andinvestigation of groundwater resources quality can lead to the correct management of these resources. So, thegoal of this study was determining the most important groundwater qualitative variables using the principalcomponents analysis and then investigation of three Kriging models performance including Simple,Universal and Ordinary models in interpolation of the most important qualitative variables defined in Bamplain. For this aim, 40 wells were selected randomly with appropriate distribution as training wells among 60wells and the rest of them were used for models testing. The results of the principal components analysisshowed that EC and TDS as the main variables have justified the most variation of variance. The conclusionof interpolation based on these two parameters showed that Ordinary and Universal Kriging methods havehad similar performance for EC estimation in training stage but in testing stage, Ordinary Kriging methodwas better than Universal method based on RMSE and MAE coefficients and for TDS interpolation,Ordinary method has had the best performance in both training and testing phase compared to the othermethods. Also interpolation results of these two variables showed that the amount of salinity in the north andnortheastern parts of the plain has been more than elsewhere in both, Ordinary and Universal Krigingmethods. This issue has been corresponded to land use changes in the study area.

کلیدواژه ها:

Groundwater quality ، Geostatistical ، TDS ، EC ، Bam plain