Zeynab Sadeghi and Hossein Pirkharrati
Abstract
In this study in order to investigate the hydro chemical groundwater quality and origin of aquifers salinity information of 15 selected wells in the region during 2013 and 2014 were used. The spatial distribution of groundwater salinity changes of Qalqachy was determined by drawing maps of in the environment of GIS software (Arc map). Evaluation of groundwater maps indicates that ion concentration in central and northern parts of plain (lake) is more than southern part of the plain (the feed zone which has minimum concentration). Comparison of the concentration of groundwater TDS, Cl, Na, SO4 with WHO standard for drinking water demonstrate that most groundwater samples have concentrations more than the specified permissible level. Also classification of groundwater chemical quality in terms of irrigation showed that most of the samples placed in the range of too salty and saline waters. Therefore, Miocene evaporative - clastic deposits, reduced rainfall and indiscriminate exploitation of coastal aquifers which cause reduction in groundwater levels, progress and salt water intrusion into aquifers, can be the reasons for the regions groundwater quality degradation.