One of the key parameters influencing sprinkler\nirrigation performance is water quality. In this study, the\nspatial variability of groundwater quality parameters (EC,\nSAR, Na?, Cl-, HCO3\n- and pH) was investigated by\ngeostatistical methods and the most suitable areas for\nimplementation of sprinkler irrigation systems in terms of\nwater quality are determined. The study was performed in\nFasa county of Fars province using 91 water samples.\nResults indicated that all parameters are moderately to\nstrongly spatially correlated over the study area. The spatial\ndistribution of pH and HCO3\n- was mapped using\nordinary kriging. The probability of concentrations of EC,\nSAR, Na? and Cl- exceeding a threshold limit in\ngroundwater was obtained using indicator kriging (IK).\nThe experimental indicator semivariograms were often\nfitted well by a spherical model for SAR, EC, Na? and Cl-.\nFor HCO3\n- and pH, an exponential model was fitted to the\nexperimental semivariograms. Probability maps showed\nthat the risk of EC, SAR, Na? and Cl- exceeding the given\ncritical threshold is higher in lower half of the study area.\nThe most proper agricultural lands for sprinkler irrigation\nimplementation were identified by evaluating all\nprobability maps. The suitable areas for sprinkler irrigation\ndesign were determined to be 25,240 hectares, which is\nabout 34 percent of total agricultural lands and are located\nin northern and eastern parts. Overall the results of this\nstudy showed that IK is an appropriate approach for risk\nassessment of groundwater pollution, which is useful for a\nproper groundwater resources management.
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