Some basic notions of theoretical hydrochemistry

This report gives the conceptual approaches to the development of the theory of the formation of natural water composition in view of the primary properties of aquatic ecosystems: the “principle of uncertainty” in the estimation of the conditions, the “continuity” of the changes proceeding, and the “plurality” of water’s natural structure and components (biotic and abiotic), as well as their interaction processes. The importance and features of each of these basical criteria for characterizing the conditions of an aquatic ecosystems are substantiated in theory.