Fig. 5. Mean exchangeable Ca (Ca_ex), Mg (Mg_ex), Mn (Mn_ex), Al (Al_ex), and K (K_ex) expressed as a percentage of the cation exchange capacity (CEC) in the B horizons of the Hermine watershed for the period 1993 to 1997, inclusively. The mean values for a given sampling date are for the nine plots. The lines are displayed to underline the seasonal trends. Error bars are standard deviations.