Influence of aeration zone and flow field on groundwater nitrate nitrogen in southwest suburb of Beijing
This paper focuses on the amount of nitrate nitrogen of the surface pollutants entering groundwater after passing through vadose zone and its influence by groundwater flow field in the southwest suburb of Beijing.Based on the numerical simu-lation of vadose zone at different locations in that area,it studies the migration law of wastewater with initial concentration of 30 mg·L-1 nitrate nitrogen in vadose zone under different stratum conditions.The nitrate nitrogen concentration changes are ana-lyzed on the 50th,100th,200th,300th,400th and 500th day at each simulation point,which shows that the nitrate nitrogen con-centration at the bottom of vadose zone at each simulation point changes with time.The interception rates of nitrate nitrogen in the aeration zone at the four simulated sites were 5.93％,10.69％,15.87％and 33.83％,respectively,indicating that the protec-tive effect of the aeration zone on groundwater from west to east in the study area changes from weak to strong.Combined with the over-standard range of nitrate nitrogen in the study area for years,the quaternary groundwater level and recharge runoff con-ditions,this paper presents the influencing factors of nitrate nitrogen in the groundwater and puts forward proposals to prevent ni-trate nitrogen pollution from further aggravating.
万方数据
维普
