Fig. 5. Time series of NO₃^––N concentrations (mg L^–1) for shallow lysimeters (solid lines) and deep lysimeters near the water table (dashed lines) for (A) California, (B) Indiana, (C) Maryland, (D) Nebraska riparian zone, (E) Nebraska corn field, and (F) Washington. Shallow lysimeters are between 1 and 2 m below ground surface, except N22b, which is 7 m below ground surface. The bracket at the top of each plot marks the 2004 growing season for that site. For California, the brackets span the interval between the first and last irrigation events. For all other sites, the brackets show the time between planting and harvesting.