Experimental and Simulation Research on the Process of Nitrogen Migration and Transformation in the Fluctuation Zone of Groundwater Level

The fluctuation of groundwater causes a change in the environment and then affects migration transformation pollutants. To study influence water level fluctuations on nitrogen transformation, physical experiments process zone were carried out. A numerical model Vadose saturated was constructed by using software HydrUS-1D. correlation coefficient root mean square error show that fits well. is used to predict different scenarios. results that, compared with fluctuating experiment scenario, when range increases 5 cm, concentration coarse sand, medium sand fine media 37.52%, 31.40% 21.14%, respectively. Additionally, decreases 36.74%, 14.70% 9.39%, varies most significantly amplitude sand; has significant impact flux nitrate little effect nitrite ammonium nitrogen, difference obvious, followed not great.