Radon in the marmot burrows. Radon Norakh sourkov. [Le radon dans les terriers d’animaux].

Résumé

The biogeochemical research of the territories of the Soviet Union where the plague Yersinia pestis is known to be present has established the anomalous concentration of heavy metals. High concentrations of heavy metals in combination with other factors can favor the propagation of epizooty among mammal's populations. It has been shown previously that the anomalous presence of the transitional d-elements of the fourth period of periodic system (titanium, chromium, manganese, iron, cobalt, nickel, copper, and zinc) correlates with epizooty among mammals (Rothschild 1994, 2000). The heavy metals very often accompany ore of uranium-thorium deposits and other radioactive elements. The subsequent geological analysis of enzootic territories of the Asian part of Russia and Caucasus has confirmed the prediction that the presence of small foci of plague correlate with uranium-thorium anomalies (Pil'nikov 2004). Logically, I've suspected, that in some burrows of the gnawers there can be a high level of concentration of radioactive gases, for example of radon. With this view, I measured radon concentration in 2000-2004 years at the burrow entrances of the Mongolian marmot (Marmota sibirica Radde, 1862) in Southeast Transbaikalia on the Chindachi's fault. The findings have confirmed the presence of high concentrations of radon in some burrows. To tests whether microclimate in the hibernating burrows of the rodents affects the concentration of radioactive gases, I measured radon concentration in various seasons. The concentrations of radioactive gas increase, when temperature of the air near a ground layer is lower than temperature of air in a burrow. This is observed during spring when marmots emerge from hibernation and during fall before animals go into hibernation. During winter months the radon concentration is expected to be even higher due to soil freezing and limited convection. The radon concentrations in the burrows of the rodents are more then ten times greater then the established norms for people working at the uranium mines suggesting that these burrowing animals have special adaptations to cope with radioactive environment.