LAUSR

The environmental status of the Eastern Ural radioactive trace (EURT) zone has been assessed by bioindication methods. A long-term (2005–2013) study of Potentilla fruticosa plants planted on three sites within the gradient of radionuclide contamination with 90Sr and 137Cs showed that, regardless of the vegetation period and year of observation, an increase in the level of radiation caused a reduction in the lamina and petiole length and an increase in the fluctuating asymmetry index of the terminal leaf lobe. The morphological indices (length, width, and area of the lamina and terminal leaf lobe; petiole length) were determined by digital image analysis using the Maplnfo software. Statistically significant differences in these indices from the control were observed only in the plants from the most contaminated area. As the radiation load increased, the interannual variability of the petiole length increased from low to high values regardless of the vegetation period. In the case of fluctuating asymmetry of the terminal leaf lobe, a significant difference was revealed between the control plants and plants exposed to radiation. Using the fluctuating asymmetry index, the environmental quality of areas located within the EURT territory was assessed as critical, while that of the control site corresponded to the norm.