CYCLIC PROCESSES IN AQUATIC ECOSYSTEMS

When analyzing the thermodynamic state of ecosystems in several Russian water bodies located in different natural and climatic zones, cyclic dynamics of changes has been revealed in entropy of various periodicities: from daily and seasonal to long-term one. For the first time, a statistical correlation was found between the 10-12- and 20-22-year cycles of the state of aquatic ecosystems with periods of increased solar activity according to the Wolf numbering. Possible reasons for the identified pattern, in particular, the hydrological features of water bodies are considered. The paper discusses a role of the hierarchical organization of the cyclic state of aquatic ecosystems in ensuring their stability and predictability.