DISTRIBUTION OF HEAVY-METALS IN HIGHER AQUATIC PLANTS OF THE UGLICH RESERVOIR

In the spring and summer of 1989, over the whole extent of Uglich reservoir, samples of several species of higher aquatic vegetation were taken to evaluate the level of accumulation of heavy metals in them. the contents of eight elements were determined on an atomic-absorption spectrometer. The results of chemical analysis showed a low degree of accumulation of metals by aquatic plants in that reservoir. The contents of most of the metals were the same in the two seasons, and only in duckweed was a higher amount of zinc noted in the spring; and of nickel for two species of pondweeds, in a number of places. Differences between species in the accumulation of metals were insignificant.