INFLUENCE OF ECOLOGICAL RISKS ON THE FORMATION OF SUCCESSIONAL BIOCENOSES IN THE RIVER-LAKE NETWORK, FISH PRODUCTIVITY AND SPECIES DIVERSITY OF ICHTHIOFAUNA

Abstract

River network is a dynamic system with the influence of a significant number of factors of natural and anthropogenic character affecting the quality and reproduction of aboriginal ichthyofauna. Despite the large area of the water mirror and the density of the river network, the aquaculture of natural water bodies is in crisis both by water quality and by weight of natural feed, reducing the number of intermediate ecotones, breeding stock. However, today there are still natural localities for the reproduction of aboriginal fish species on the river Horyn (Derazhne, Stepan, Dubrovytsia, Vysotsk), on the river Sluch (floodplain in the alignment of village of Kolky with floodplain lakes). Populations of carp, silver carp, individual species of paddlefish penetrating from farm fish farms, in particular in the alignment of below smt. Derazhne, village Shubkiv are marked. The paper identifies environmental risks affecting the species diversity of native aboriginal ichthyofauna, fish productivity and the formation of successional changes in hydro bionts. It is clearly necessary to develop a ″Small Rivers and Lakes″ program to address the risks of impact on the aquatic environment and rehabilitation and reproduction of species diversity of natural water bodies (natural aquaculture) as a component of the trophic chain system. As a direction of obtaining marketable fish products, a combination of fish floodplains and ponds (separation of part of shallow water reservoirs) as well as a combination of specialized farms for feeding carp fish, white cupid, pike perch, even fishing teams worked. The basis of fish farming were ponds (Dubno, Ostrig, Peresopnytsia, Olyka). However, when the ecosystem of rivers is improved, risks are minimized, natural fish productivity will be restored.