Analysis of the Equilibrium State of Lake Fish Community Based on Its Dynamic Phase Portrait

Resumo

Abstract—The results of a study of the fish community and population in some Russian lakes (Lake Imandra on the Kola Peninsula, Lake Syamozero in Karelia, and Lake Vozhe in Vologda district) based on the phase-portrait method are presented. This method reveals stable-state zones for the fish community and the level of deviation from this level under the influence of various anthropogenic factors. The main factors are water pollution (Lake Imandra), eutrophication, and invasion by new species (Lake Syamozero), as well as the introduction of the sander (Lake Vozhe). The removal of negative factors leads to ecosystem stabilization.