عنوان مقاله [English]
Agricultural irrigation with treated wastewater effluent may be used for crop production, but due to elevated of certain contaminants (e.g. nitrate or nitrite) may adversely impact the quality of groundwater. This research was carried out to investigate the transfer of nitrate in deep soil that was planted with corn fodder crop using treated effluent from the sewage treatment plant in the city of Neyshabur during 2012-2013. The study data were collected in pot cultivation with the same condition and under a completely randomized design. The irrigation with wastewater effluent and conventional raw water was performed at four levels comprised of: 100% irrigation capacity and 80% irrigation capacity for two irrigation periods of 8 and 10 days and 3 replications. The result of this study showed that irrigation levels and irrigation periods affected the absorption of nitrate by corn. Comparison of the amount of nitrogen in wastewater effluent and conventional raw water before and after irrigation showed that the nitrate absorption in the plant was low (below the standard level) and there is no significant health issue for the users of the corn forage components in the food chain. Also, the average nitrate concentration (on mass basis) of wastewater effluent after irrigation (drainage water) was about 64 mg/kg and the nitrate content in the soil under irrigation was about 59 mg/kg. Irrigation of corn with treated wastewater does not increase the health hazards of the crop and the soil, but there is still a high risk of nitrate pollution for the water resources in the area.