ECOLOGICAL STATUS OF SURFACE WATER IN TERMS OF ENVIRONMENTAL PROTECTION INDICATORS

Current issues related to pollution of aquatic ecosystems necessitate an assessment of the water quality of the Danube River based on environmental protection parameters. This paper analyzes the concentrations of orthophosphate (PO₄–P) and nitrate (NO₃–N) in water, in accordance with the Rulebook on the National List of Environmental Protection Indicators (Official Gazette of RS, No. 37/2011), at the Radujevac monitoring station, which represents the river’s exit point from Serbia. The calculated mean annual concentrations of the observed parameters (PO₄–P = 0.129 mg/L and NO₃–N = 0.96 mg/L) correspond to water quality class III and class II, respectively. The ecological status of the Danube River at the Radujevac station is classified as moderate (class III), due to the orthophosphate concentration exceeding the reference value. These results highlight the need for measures aimed at preventing pollution and improving the water quality of the Danube River in the context of environmental protection.