Северский Донец

Purpose.The testing the method of environmental assessment of surface water quality in terms of the use of biological indicators. Methods. Biological and hydrobiological. Results. To evaluate used quantitative and structural indicators of zoobenthos (TBI, BBІ), zooplankton (saprobity index) and phytoplankton (saprobity index, biomass and chlorophyll «a»). The results of the environmental assessment of the quality of waters of the river Seversky Donets River and its major tributaries within the Kharkiv region on biological indicators of surface water quality, which are used in the method of environmental assessment of surface water quality (edition of 2012). The values of the generalized biological index (ІБ) of the average values of indicators show that the water researched areas of the rivers belong to the II and III water quality classes and graded as "good" and "moderate" as "clean" and "contaminated" by the degree of purity (contamination). Areas with the worst values of biological indicators summarizing experiencing the greatest anthropogenic load. BBІ more sensitive reacted to anthropogenic pressure and had a larger range of changes than TBI. Conclusions. In assessing the ecological status of water bodies is absolutely necessary to consider the role of the biological component to display the actual state of aquatic ecosystems. In assessing the ecological status of water bodies is absolutely necessary to consider the role of the biological component to display the actual state of aquatic ecosystems, which reflects the degree of wellbeing ecosystem of the water body as a whole.

The spatial distribution of heavy metals in abiotic components of aquatic ekosystems rivers depends pri-marily on landscape (natural) features of the area which is formed by runoff. Determining for the rivers and their areas under human influence becomes surface runoff from urban areas, wastewater and recycled water intake with feeding groundwater.The basic factors that influence the formation of the quality of the sediments in the river Seversky Donets and the accumulation of heavy metals were reviewed. Determined that a higher content of metals in the sediments have an average with a high content of silt and clay, which can be explained both by the chemical composition of the clay soil, and the ability to absorb himself in the metal from the aqueous phase.