Evaluation of quality and quantity changes of underground water in Fasa plain, Fars (2006 - 2013)

In this research, changes trend of quantity and quality of underground water and also trend of changes in drought in Fasa plain- Fars that is one of the most important population centers in Fars province evaluated. In order to this, data of 52 wells from plain in period 2006 to 2013 and precipitation data of Fasa station from 1967 to 2013 was used. To evaluate of data and assessment of time trend of them Aquachem and R softwares were used. Results of evaluation of changes trend in groundwater level showed that groundwater level has had decreasing trend in the recent two decades. So that average annual decline of water table level is about 0.95 meters per year. Results of evaluation of water quality changes in study period showed that the all quality parameters have had an increasing trend. Increasing trend of changes in Cl, Ca and TH in 90% level and in EC in 95% level are significant. This reflects that the quality of underground water has a decreasing trend. Evaluation of changes trend of drought showed that repetition of meteorological drought occurrence in recent decade (2003-2013) compared to the past four decades (1967- 2003) has been 2.5 times.