Entropy approach to assessment of the ecological state of a water course

Abstract

It was established that the water does not meet the upper limit of the 1st quality class according to DSTU 4808:2007 by all parameters except BOD₅, COD and suspended matter. There is a decrease in the level of BOD₅ at posts in the city of Dnipro, which indicates the entry into the watercourse of substances that inhibit biochemical processes and a gradual increase of this indicator at the exit from the city and further downstream, which indicates the entry of organic substances. The oxygen content decreases in the part of the watercourse located in the city  and increases in the middle and lower part of the reservoir. There is also a trend of growth of sulfates, nitrogen compounds, phosphates, SPAR and COD for control points located within the city of Dnipro. The highest values of the entropy index of water quality are characteristic of points are located at a considerable distance from industrial centers 

Conclusions.  The main water pollutants are nitrites, nitrates, phosphates and suspended solids. It can cause a negative impact on health  and also accelerates the eutrophication of the water body. A negative impact of agro-industrial production on the ecological condition of the Dnieper Reservoir is observed.