EN
This study investigated 14 lakes situated in the Borecka Forest, and the analyzed data covered a period of 10 years. The examined water bodies are at low risk of eutrophication. Three factors explaining 79.1% of total variability in the analyzed natural lakes were identified: 1 – morphometry – use of catchment area, 2 – water chemistry, 3 – lake/catchment area. Those factors determined the patterns of macrophyte distribution in the lakes. The variables applied in the CCA ordination plot explained around 59% of the total variability in plant distribution patterns in the examined lakes. Chlorophylla (chla ) was a statistically significant parameter, which explained 12.4% of the total variability in plant distribution patterns in the analyzed lakes. Morphological, physicochemical and catchment area variables have a significant effect on the development of vegetation in the Natura 2000 sites. The results of this study provide the basis for formulating general management guidelines for the investigated lakes and their catchments, which belong to the Natura 2000 ecological network of protected areas. A comprehensive protection plan should be proposed for interdependent habitats. Forest cover in the lakes’ catchment areas should be maintained or expanded, and the share of intensively farmed land should be reduced. Clear cutting in areas adjacent to the lakes should be prevented, and the inflow of biogenic elements, nitrogen and phosphorus (which affects Chla concentrations) should be reduced. The above goals can be achieved, among others, by preserving the existing water relations and species composition of tree stands in the lakes’ catchments areas.