Fig. 3. Surface water and soil pore water profiles of ammonium-N concentration with depth (1-cm interval) in Wetland System 1 (WS1, Cells 1 and 2, Schoenoplectus/Scirpus/Juncus) and Wetland System 2 (WS2, Cells 2 and 3, Typha/Sparganium). Solid horizontal lines at depth = 0 indicate the soil–water interface boundary. Each data point is the mean of duplicate samples.