Pedosphere 18(5): 628--637, 2008
ISSN 1002-0160/CN 32-1315/P
©2008 Soil Science Society of China
Published by Elsevier B.V. and Science Press
Migration of infiltrated NH4 and NO3 in a soil and groundwater system simulated by a soil tank
WANG Chao and WANG Pei-Fang
State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Key Laboratory of Integrated Regulation and Resource Department on Shallow Lakes, Ministry of Education, Environmental Science and Engineering College, Hohai University, Nanjing 210098 (China). E-mail: cwang@hhu.edu.cn
ABSTRACT
      The infiltration of water contaminants into soil and groundwater systems can greatly affect the quality of groundwater. A laboratory-designed large soil tank with periodic and continuous infiltration models, respectively, was used to simulate the migration of the contaminants NH4 and NO3 in a soil and groundwater system, including unsaturated and saturated zones. The unsaturated soil zone had a significant effect on removing NH4 and NO3 infiltrated from the surface water. The patterns of breakthrough curves of NH4 and NO3 in the unsaturated zone were related to the infiltration time. A short infiltration time resulted in a single sharp peak in the breakthrough curve, while a long infiltration time led to a plateau curve. When NH4 and NO3 migrated from the unsaturated zone to the saturated zone, an interfacial retardation was formed, resulting in an increased contaminant concentration on the interface. Under the infiuence of horizontal groundwater movement, the infiltrated contaminants formed a contamination-prone area downstream. As the contaminants migrated downstream, their concentrations were significantly reduced. Under the same infiltration concentration, the concentration of NO3 was greater than that of NH4 at every corresponding cross-section in the soil and groundwater tank, suggesting that the removal effciency of NH4 was greater than that of NO3 in the soil and groundwater system.
Key Words:  breakthrough curve, migration, NH4, NO3, soil tank experiment
Citation: Wang, C. and Wang, P. F. 2008. Migration of infiltrated NH4 and NO3 in a soil and groundwater system simulated by a soil tank. Pedosphere. 18(5): 628-637.
View Full Text



Copyright © 2024 Editorial Committee of PEDOSPHERE. All rights reserved.
Address: P. O. Box 821, 71 East Beijing Road, Nanjing 210008, China    E-mail: pedosphere@issas.ac.cn
Technical support: Beijing E-Tiller Co.,Ltd.