Miscible displacement of nitrate and ammonium in soil columns

Abstract

The displacement of nitrate fertilizer by distilled water under saturated conditions and at different average flow velocities in one – dimensional soil columns is studied to observe the behavior of the nitrogen in transport processes. Breakthrough curves of nitrate were comparing to the ammonium breakthrough curves symmetrical with all aggregate sizes. The biggest influence on the nitrate retention had 0.63–2 mm fraction, where 30–50 % of the total mass was preserved. The biggest influence on the ammonium transport had its ability to fixate on the negative charged particle surfaces. Breakthrough time for nitrate and ammonium was the shortest with 2–4 mm aggregate size.

Keywords

• nitrate
• ammonium
• column experiments
• mass recovery
• breakthrough time
• porous media