Groundwater quality degradation of an aquifer in Iran central desert

Hydrochemical quality of groundwater in an aquifer in central Iran adjacent to central Kavir desert was analyzed in this study. The dominant type of groundwater in the area is Na + K_Cl + SO4 which is mainly different from the common type of fresh waters in Iran (Ca_HCO3). The spatial distribution of anions and cations as well as EC obeys an increasing pattern eastwards. Due to high concentrations of SO42−, Cl−, K+ and Na+ all of the water samples are not categorized in suitable ranges for drinking use. Regarding agricultural use suitability of regional groundwaters, except for 4 samples in central parts of the study area which show high salinity hazard, all other samples are absolutely not applicable for agriculture due to extremely high values of EC. Illegal groundwater pumping mainly for regional agricultural use during recent years has caused groundwater quality degradation due to saline water intrusion from eastern areas (central Kavir desert and salt lake) and connate water upcoming from deeper aquifers. As the main use of water in the study area is contributed to agriculture, implementing modern mechanized irrigation techniques accompanied by planting crops with low water demand and high tolerance against salinity may be recommended.