ABSTRAKT

Data of long-term hydrochemical observations on rivers of the upper Ob' catchment area (West Siberia, Russia) in various periods of the 20^th century (1954−1993) are generalized and discussed. Changes of the ion-salt composition of waters (ions ÍÑÎ₃⁻, SO₄²⁻, Cl⁻, Ca²⁺, Mg²⁺, Na⁺+K⁺, and total ions) under the impact of industrial effluents, at different volumes of annual runoff, debits, and in different phases of the hydrobiological regime are demonstrated.