EN
Mineral composition of water in Roztoka Odrzanska was studied between 1991-1993. The studies showed that the mineral composition of water depends mainly on the magni-tude of the river Odra flow. The increase in mineralisation of Roztoka Odrzanska water was found to be coinciding with the decline of the monthly mean Odra flow below 395 m3?s-1. Specific changes of mineral composition occur in the mixing zone of fresh and saline water. They can be related to coagulation-peptization processes of colloides and sorption processes which use up SO2-, and Mg2+ ions.