Analysis of Groundwater Quality Spatial Distribution Pattern and Spatial Variations in Electrical Conductivity (Case Study: Hamadan Province)

Changes in the quality of underground resources for various reasons, especially the unconventional use of these resources can have devastating effects on the environment.In this research, groundwater quality parameters including electrical conductivity, total soluble solids, acidity, sodium adsorption ratio, hardness, bicarbonate, chloride, sulfate, calcium, magnesium, sodium, potassium, and the sum of anions and cations were used. in this research, groundwater quality data related to piezometric water wells affiliated to the Hamadan Regional Water Company for four-year periods in 2009, 2013, 2017, and 2020 in the plains of Hamadan province have been used. The results of Moran and coefficient of gery show that the spatial distribution pattern of all water quality parameters in 2009 and 2020 is random and for the parameters of electrical conductivity and sodium adsorption ratio in 1992 and 1996, respectively, with a high level of confidence of 95% and 90%, respectively, it had a spatial distribution with a cluster pattern with high values. To investigate the spatial variations of electrical conductivity using the Kriging method, water quality maps in terms of electrical conductivity parameters for the years 2009, 2013, 2017, and 2020 have been prepared. The map of electrical conductivity changes prepared from 2009 to 2020 years shows that the amount of electrical conductivity in the city of Hamedan (Qahvand) and Razan and Kaboudar Ahang plains has more increasing changes, which indicates a decrease in groundwater quality in the case study area. Therefore, planning is necessary to correct the decline in groundwater quality.