[PARASITE FAUNA AND STRUCTURE OF PARASITE COMPONENT COMMUNITIES IN THE MINNOW PHOXNUS PHOXINUS (LINNAEUS, 1758) IN AN...

In June 1992 and July 1996, 238 minnow specimens of the 2+--3+ age were collected from 5 parts of the Kolva River and studied using the standard technique of the general parasitological dissection. Comparative analysis of parasite fauna and the structure of component parasite communities in the minnow from ecologically safe and variably polluted parts of the river was performed. The analysis had demonstrated that the increase in the water pollution by domestic wastewater, washings of fertilizers from agricultural fields and private country houses, cattle farm drains (Dorovskikh et al., 2005, 2008), and oil results in the change of dominant parasite species of the minnow, alteration of the sum of errors in the regression equation characterizing the spread of biomass values of the species forming the parasite community, changes in the "graphic" structure of the community, and alteration of the index D(E)'. It is proved, that the high concentration of nutrients has a destructive effect on natural systems, and, at the same time, causes the process of self-organizing, leading to the alteration of the community structure. As soon as even a small part of nutrients is stopped to come into the reservoir, and the quality of environment is restored, the community restores its structure.