Åsa Danielsson

Inorganic Nutrients in Swedish River: Seasonal Variation of Inorganic Nutrients (Dsi, Din and Dip) Concentration in Swedish River Åsa Danielsson

Rivers have been playing most important role as fresh water source and medium of nutrient transportation from terrestrial to aquatic ecosystem. Inorganic nutrients (DSi, DIN and DIP) are plant available mostly control the productivity of aquatic ecosystem. Study of dissolved inorganic nutrients concentrations in 12 Swedish rivers of different basin characteristics demonstrated both similar and varying behaviour from river to river and from season to season depending on catchment hydrology; land use and geology. Highest concentration did not coincide with the highest runoff. High DSi concentration observed in the unperturbed rivers however, high DIN and DIP concentration observed in agriculture dominated river followed by river basin dominated by industrial and urban activities. DSi and DIN concentration observed high in winter and decreased through spring to reach lowest in summer. DIP concentration although found low in summer but high concentration observed in early spring and early autumn. Rivers with low average runoff positively correlated with DSi and DIN concentration however, DIP demonstrated weak correlation.