摘要：In order to understand the nitrate contamination in ground waters of Ippatla village, Kadapa (Dist), 20 ground water samples were collected and analyzed for different parameters like, pH, electrical conductivity (EC), total dissolved solids (TDS), hardness, K, Ca, Na, Mg, Cl and NO3.The main objective of this study is to know about the ground water quality especially nitrate in the study area. In the study area the pH of water varies from 6.7 to 8.4 indicating alkaline in nature. The electrical conductivity ranging from 450 to 4500 micromhos/cm, total hardness varies from 150 to 780 mg/l, TDS varies from 220 to 1200 mg/l, calcium values ranges from 45 to 280 mg/l, magnesium ranges from 32 to210 mg/l, sodium ranges from 32 to 210 mg/l and potassium ranges from 0.3 to 12 mg/l. In the study area, the analysis of ground water shows that the concentration of nitrate (as NO3) varies from 5 mg/l to 390 mg/l. The average nitrate concentration in ground water of the study area is 148.7 mg/l, which are significantly high as compared with guideline recommended by WHO. The concentration of nitrate is more than permissible limit (45 mg/l) in 15 water samples out of 20 samples in the study area. 60% of samples in the study area exceeded the upper limits 45 mg/l. Deeper wells have more NO3 concentration than shallow ones. Scatter plot shows the positive correlation between nitrate and chloride emphasizes that fertilizers are the probable source for the high values of nitrate and chloride. Nitrate and chloride concentrations in ground water were found to be lower in areas where the land had remained fallow for longer period. However, NO3 and Cl concentrations were found high in wells located in agricultural fields and where the land is in continual use. Thus, increased irrigation and fertilizer use caused increased nitrate and chloride concentrations in ground water of the study area. Hence there is a need to work out the optimum quantity of fertilizers that should be used for a particular crop in a particular area and to educate the farmers on this aspect
