plants and developed chemical industry. Municipal waste water treatment plants and agricultural activities are also considerable sources of pollution. Ecosystem of the lower reaches of Daugava is strongly influenced by dams and reservoirs of three hydroelectric power plants: Plavinas, Kegums and Rīga. Belarus also has a goal to construct a cascade of four hydroelectricity plants on the Daugava River (Polotsk, Vitebsk, Beshenkovichi, and Verkhnedvinsk) with a total capacity of up to 130 MW untill 2020. Currently Vitebsk and Polotsk HPPs are under construction and currently they operate on a test regime. Mean water flow: 791 m3 s-1 Area specific P inputs 18 kg km-2 Area specific N inputs 450 kg km-2 Trends in the export: The Daugava River In 2014 flow was only 53% of the long term mean flow and nutrient export was also less than 60% of the long term mean: 20,000 t N and 757 t P. There was a statistically significant increase in P export from 1995 to 2014 (Fig. 6a). The correlation between flow and export weaker than respective correlation of the Göta and Kemi rivers (Fig. 6b).
plants and developed chemical industry. Municipal waste water treatment plants and agricultural activities are also considerable sources of pollution. Ecosystem of the lower reaches of Daugava is strongly influenced by dams and reservoirs of three hydroelectric power plants: Plavinas, Kegums and Rīga. Belarus also has a goal to construct a cascade of four hydroelectricity plants on the Daugava River (Polotsk, Vitebsk, Beshenkovichi, and Verkhnedvinsk) with a total capacity of up to 130 MW untill 2020. Currently Vitebsk and Polotsk HPPs are under construction and currently they operate on a test regime. Mean water flow: 791 m3 s-1 Area specific P inputs 18 kg km-2 Area specific N inputs 450 kg km-2 Trends in the export: The Daugava River In 2014 flow was only 53% of the long term mean flow and nutrient export was also less than 60% of the long term mean: 20,000 t N and 757 t P. There was a statistically significant increase in P export from 1995 to 2014 (Fig. 6a). The correlation between flow and export weaker than respective correlation of the Göta and Kemi rivers (Fig. 6b).