Fig. 2
From: Modelling the effect of different agricultural practices on stream nitrogen load in central Germany
The measured discharge and nitrate-N concentrations for the period 1983–2003. The discharge was measured at a daily time interval. The NO3˗N concentrations were only measured at daily time steps during the period 1997–2003 (green circle points), while for the earlier periods 1983–1987 and 1989–1996, they were measured at weekly and bi-weekly time steps, presented here with blue diamond and red triangle markers, respectively