Recent Levels of Radionuclide Contamination in the Eastern Ural Radioactive Trace and Biological Effects in Local Populations of Plantago major L.

Abstract

The results of the study have shown that the stocks of 90 Sr and 137 Cs in the frontal part of the EURT are 6700-15000 and 200-400 kBq/m 2 , respectively. The coefficients of their accumulation in different herbaceous plant species in this impact zone are lower than in other areas. The accumulative capability of plants has probably decreased in the course of selection as an adaptation to the effect of radiation. The viability and growth parameters of Plantago major L. seeds from the EURT zone are similar to those of seeds from the background sample. Cenopopulations chronically exposed to radiation are characterized by a higher mutation rate in the progeny and an unstable response to additional acute irradiation in most characters studied. A high level of inbreeding is observed in all P. major cenopopulations of plantain. The cenopopulation of the impact zone is characterized by a lower variation of allozyme loci, which may be a result of stringent selection for individuals better adapted to the complex of conditions existing in its habitat.

Time-dependent changes of the physiological status ofBromus inermisLeyss. seeds from chronic low-level radiation exposure areas

“…There were also differences in maximal and minimal survival rates between different individuals from within the EURT area (January, July, and September). Similar instable pattern to the resistance to radiation has already been shown in the analysis of the dose-effect curves in Plantago major L. (Pozolotina et al, 2005) and Stellaria graminea L. from the EURT area (Pozolotina et al, 2010a).…”

Radionuclides in terrestrial ecosystems of the zone of Kyshtym accident in the Urals

“…Previously we have shown (Pozolotina et al, 2005) that in the impact zone, concentrations of the main contaminator ( 90 Sr) in aboveground parts of the herbaceous plant species were by 3-4 orders of magnitude higher than those in buffer and background zones, but the corresponding coefficients of accumulation were significantly lower. This may be due to either physical-chemical state of the radionuclides in soils, or due to biological peculiarities of plants adapted to life at the contaminated conditions.…”

“…Table 2 demonstrates that in the impact zone dose loads upon embryos per month due to the radionuclides incorporated in seeds are by 3-4 orders of magnitude higher than those in the background samples (the significance of differences between populations, c 2 ¼ 18.33, df ¼ 2, p ¼ 0.0001). High variety of absorbed doses upon seeds in the impact zone may be related to (Pozolotina et al, 2005).…”

“…Absorbed doses within the EURT might be referred as the ''low doses'' category. Nevertheless, due to longtermed irradiation, they were shown to cause different biological effects described in a series of publications (Shevchenko et al, 2000;Pozolotina et al, 2005;Ul'yanova and Pozolotina, 2006).…”

Radioactive inventories within the East-Ural radioactive state reserve on the Southern Urals

“…Typically, they led to reducing radionuclides stocks in the soil. To evaluate intensity of radionuclides geochemical migration we previously studied geochemical couplings that were characterized with the highest diversity of plant communities types; this data are represented in the study [5]. At early stages of the trace formation the radioactive fallouts were hampered by the plant cover and thin topsoil.…”