Blanice River nature reserve

In this article, we sought present quantitative evidence of water quality improvement within a freshwater protected area. The data exhibits long-term monitoring of surface water quality concentrations for sampling sites along headwaters (S1-S6) between 1989 and 2016 and at the main tributary (DSP) of the Blanice River in the Czech Republic from 1986 to 2019 (see Fig. 1a and Table 1 in manuscript for details on sample locations). This data was used for linear regression (see Methods in manuscript and Supporting information Methods S2 for details). Water samples were collected using conventional sampling protocols and analyzed according to the standardized methods of the Czech National Standards Criterion. Water quality data from the period 1986-2000 was provided by unpublished reports of the state nature conservation agencies (for a list of sources, see Supporting Information Figure S1) and data from the period 2000-2019, water quality was provided by T. G. Masaryk Water Research Institute.