Okhrimenko O. The Use of Hуpophthalmichthys molitrix (Val.) for providing the ecological balance in the ponds-coolers of Nuclear Power Plants

The thesis is devoted to researches of role of white silver carp as the biological meliorator in the water ecosystems of nuclear power objects for the improvement of their ecological state. The economic usage of such water bodies must be realized by scientific reasoning of their yearly fish-planting based on researches of species composition, quantity, biomass of basic components of forage base, bioproduction, peculiarities of ecosystem functioning. Environmental assessment of ZNPP pond-cooler's ecosystem as base model object based on researches of interplay of abiotic and biotic components was made. It was found that water of pond-cooler belongs to ІІІ class 4 category slightly polluted ?-mesosaprobic zone. It was proved stressed state of water ecosystem by bioindication methods. The expediency of biological melioration of NNP's ponds-coolers by introduction the white silver carp which can effectively reduce quantity of blue-green algae by transformation them in valuable ichthyomass was determined. It is proposed to planting two-year-old-fish white silver carp with the body mass about 100-200 gr with fish density 292 ind/ha into nuclear power object's ponds-coolers that allows to reach fish productivity about 293 kg/hа. Economic efficiency of the biomelioration can be about 72% because of low cost price and high general growth of introduced fish.