عنوان مقاله [English]
نویسندگان [English]چکیده [English]
Seasonal maps of groundwater pollution may be deployed in respective aquifer management. The aims of this research were to study the seasonal fluctuations in concentration, spatial variability, and zonal maps of nitrate and phosphate in Shahrekord Aquifer. For this purpose, 100 agricultural wells were sampled in the spring, summer and fall of 2011 and analyzed for nitrate and phosphate. Kriging was used for zonal mapping of both pollutants. Mean concentrations of both pollutants varied over seasons. Suitability of spherical variogram model in the spring and Gaussian variogram model in the summer and fall shows that spatial patterns of nitrate and phosphate change along with season of the year. Highly nitrate-polluted areas maximized in the spring and then decreased towards the fall. In the fall, about two-third of the aquifer, particularly northern zone, contained between 0 to 20 mg/L of nitrate. Phosphate-polluted area of the aquifer was at maximum level in the fall, decreased during the spring and minimized in the summer. Therefore, we conclude that concentration, spatial distribution pattern and zonal maps of both nitrate and phosphate in Shahrekord aquifer changes with season.