Radioecological Studies of the Marsh Frog in Reservoirs of the Middle Urals.

A study of the accumulation of radionuclides ⁹⁰Sr, ¹³⁴Cs, and ¹³⁷Cs by the marsh frog Pelophylax ridibundus Pall., 1771 living in the areas of the reservoirs of the Middle Urals has been carried out. The variability of size and mass indicators and concentrations of radionuclides in animals in the surveyed area is noted. Increased concentrations of ¹³⁷Cs and ¹³⁴Cs are detected in some amphibian representatives when compared with average values. A significant decrease in the concentration of ⁹⁰Sr in frogs with an increase in raw body weight is found in much statistical material. An analysis of the data obtained on the concentrations of ⁹⁰Sr and ¹³⁷Cs in frogs of different sexes did not reveal a significant difference in the accumulation of either radionuclides between male and female animals or ⁹⁰Sr by striata and strieless amphibians. It is shown that radionuclides ⁹⁰Sr and ¹³⁷Cs enter the body of an animal from water much more than from the ground, while, with an increase in the concentration of radionuclide in the habitat, the coefficients of their transition into the animal body decrease. [ABSTRACT FROM AUTHOR]