| Abstract: | This paper provides for the first time comparative assessment of the contents of 70 chemical elements occurring in the aquatic
environment in water, phytoplankton, and zooplankton. The assessment was made using modern highly sensitive methods. The studies
were performed at Beloyarskoe Reservoir, a manmade freshwater lake situated in the Middle Urals that has been studied in detail.
The chemical elements were ranked in groups differing in the accumulation coefficient (AC) values for the phyto- and zooplankton.
The comparison revealed that for the vast majority of chemical elements, the AC values were higher in zooplankton (53, or
76%) than in phytoplankton (17, or 24%). The average AC values for zooplankton (∼740 000) exceeded that for phytoplankton
(∼68 000) by more than 10 times. It was found that some elements had very high AC values in zooplankton compared to phytoplankton.
For instance for Nb, the ratio ACzoo/ACphyto was 1 200 000; for B, Ta, Sn, Lu, U, 300 000–500 000; for Sb and Y, 100 000–130 000; for La and Nd, 80 000–85 000; for Mo,
Cd, Pr, Gd, Dy, Sc, Se, Bi, 20 000–30 000; and for Pd, Hf, Sm, Sb, Er, As, 10 000–20 000. It is concluded that zooplankton
is sometimes more suitable for the biogeochemical indication of the pollution of natural water bodies, because the AC values
for most elements are much higher in zooplankton than in phytoplankton and the total plankton. Considering the high assimilability
of microelements and radionuclides, the plankton may serve not only as an indication but also as the mean of regulated purification
of waterbodies from these elements. |
