Plant pigments as indicators of water transformation in the upper Volga Chain of reservoirs

Results of studying spatial and temporal variability in plant pigments in the Volga River water from the upper sections of the Ivankovo Reservoir downstream to the Rybinsk Reservoir Main Reach, as well as the applicability of different groups of indices of the absolute and relative concentration of pigments (chlorophylls, phaeo-pigments, and carotenoids) are presented. To differentiate water masses, these pigments have been assessed using the standard spectrophotometric method. It has been found that waters of individual river sections, singled out according to their hydrological features, and waters of different reservoirs on the whole can be reliably distinguished according to the concentration of pigments in the plant suspension.