Analysis of Nitrate Nitrogen Pollution in the Groundwater of Typical Agriculture Field of Weishan Irrigation Area

To seek the way to reduce the groundwater pollution risk in the Weishan irrigation area,typical agricultural field was selected,and in-situ sampling was carried out at different depths of groundwater.Vertical distribution pattern of nitrate in the agricultural field was analyzed according to the nitrate content in the samples,and nitrate nitrogen pollution condition was evaluated,and the existing characteristics of different nitrogen forms were analyzed also.The results show that the nitrate nitrogen content in shallow groundwater of the irrigation field significantly has exceeded the national drinking water standard,while that in deep groundwater is within the standard.Organic nitrogen is the main existing form of field nitrogen,but its solubility is quite low.The content of nitrate nitrogen is obviously higher than ammonium nitrogen,and the adsorbability of ammonium nitrogen is high,while the leaching risk of nitrate nitrogen is high.Delaying the nitrification process of ammonium nitrogen may be an effective measure to reduce nitrate pollution.