TY - JOUR N2 - Climate change, manifested by long term periods of drought to heavy rainfall, may remarkably modify river flow regimes. We hypothesize that flow prevailing in a given year determines water chemistry of the Carpathian Raba River above and below Dobczyce Reservoir (southern Poland), used for drinking purposes. Based on the mean annual river flow for years 1991‒2017, hydrologically dry (HD), hydrologically average (HA)and hydrologically wet (HW) years were distinguished. We found significant differences in the values of most studied physicochemical parameters of river water above and below the reservoir between studied hydrological years (for a period of April‒November). In HD years, the water above the dam had significantly higher temperature and values of conductivity (point pollution source, groundwater inflow), while lower ones of nutrients NO3- and P-tot (diffuse pollution) compared to those in HA and/or HW years. The best GLM models for mean monthly flows above and below the dam include 3‒5 factors among which conductivity and NO3- concentration were always present. The reservoir in different ways influences the water chemistry below the dam in HD, HA and HWyears. The impact of flow on the water quality in hydrologically varied years is discussed. The obtained results are important for appropriate management in catchment basins of mountain rivers and the protection of dam reservoirs against the eutrophication processes in changing climate and flow regime. L1 - http://www.czasopisma.pan.pl/Content/122582/PDF/Archives%20vol%2048%20no1pp31_40.pdf L2 - http://www.czasopisma.pan.pl/Content/122582 PY - 2022 IS - No 1 EP - 40 KW - flow KW - physicochemical parameters KW - Carpathian river KW - impact of dam A1 - Szarek-Gwiazda, Ewa A1 - Gwiazda, Robert PB - Polish Academy of Sciences VL - vol. 48 DA - 07.03.2022 T1 - Impact of flow and damming on water quality of the mountain Raba River (southern Poland) ‒ long-term studies SP - 31 UR - http://www.czasopisma.pan.pl/dlibra/publication/edition/122582 T2 - Archives of Environmental Protection ER -