Humic Acids in the Inflows to the Fláje Reservoir after Deforestation of its Watershed

Today only 35% of the catchment area are covered by forests after deforestation, as compared with the original 70%. In connection with that, the concentration of humic matter has decreased from the original 8 mg/1 to 4 mg/1. The analysis of these changes is facilitated by the linear regressions of a high significance which exist between the COD-Mn and humic acid concentration and the colour. Parallel to deforestation, also the nitrate concentration increased, which, however, can be explained by higher nitrogen concentrations in precipitation.