In this paper, the transformation rate of the physicochemical aquatic environment of Dzierzazna catchment were presented. Based on long-term characteristics the temperature, specific conductance, alkali level, dissolved oxygen, turbidity and its seasonal distribution (10 measurement points) the monthly averages and yearly medians also Markham’s seasonality indexes are counted (years 2003–2013). The average water pHs and dissolved oxygen haven’t big spatial and time diversity (low seasonality index: IS = 2.6–13.0%), in contrast to the turbidity and temperature of water (higher seasonality index: IS = 21.4–35.5%). The temperature maximum fell in in July and the amplitude increases with the passage up the river, because of several water reservoirs. The time of other characteristics concentration falls between early April and mid-May. The electrical conductivity showed that the maximum SEC values are observed in winter (till 21.3 mS ∙ cm–1 in A2 motorway sewages), as same as in waters of Dzierzazna river system (360–480 μS ∙ cm–1). The conductivity has also greater seasonal variability and spatial diversity in catchment.

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