The Study of Salinity Changes of Groundwater Sources in Sarab Plain

Sarab Plain is located between Sabalan Mountain and Bozgoosh chain. This plain has rich groundwater resources, but waters asre saline due to movement toward the center of plain. This study assesses chemical quality of Sarab groundwater, and studies salinity changes of groundwater sources, in a duration of a decade (1999- 2008). It uses the result of chemical analysis 45 deep and semideep wells in plain including EC, SAR and Cl indexes. It shows the distribution of quality indexes with mapping quality maps. The results of this study show that piedmonts of around plain have low and very low saline groundwaters, and the rate of salinity increases toward center and west of plain. Also, variation of EC index show that the rate of fresh groundwater has declined from June 1999 until June 2008. In this period low salinity of groundwater has inceased to 14.5%