Study of Local and Temporal Changes of Groundwater Quality Standards of Hamedan-Bahar Plain Using (GIS) over a 10 Year Period

Groundwater is the valuable resources for drinking, agriculture and industry uses in the most regions of Iran. Groundwater qualitative changes can be created by human activity and industrial development. Study of these resources is necessary in order to maintaining and improving their quality. The objective of this study is zoning and regional the specification parameters point of the case study. Finally determined the best method for zoning the each of the variables and permitted and infect areas in agricultural uses.  In addition behavior variables were investigated in the 10 year period of time.

Qualitative data of Hameda-Bahar plain in Ten-year period were used in this study. Variables such as EC, TDS, SAR, HCO3, PH, Cl & Na evaluated by Geostatical methods include of Ordinary Kriging(OK),(by Circular, Gaussian, Exponential and spherical Semivariogram Modeling) and the specific methods include inverse distance weights (IDW), radial basis functions (RBF), global polynomial interpolator (GPI) and local polynomial interpolator (LPI), were zoning with ARCGIS9.3.

Results indicated that the best method to zoning the qualitative parameters were IDW (EC), RBF (TDS), OK exponential semivariogram (HCO3), IDW (PH), RBF (Cl), OK exponential semivariogram (Na) and RBF (SAR) in Hamedan-Bahar plain. According to the best method the zoning of parameters was done for 2005, 2009 and 2014 years.

Results showed that Na had the maximum changes in ground water during the study period. The area percent for this parameter increased 3.21% from 2005 to 2014.