Monitoring of radionuclide contamination of plants in the western part of Volyn Polissya (Ukraine) during 1994–2007

Abstract

Abstract. We present the main results of our more than decade-long monitoring of 137 Cs content in berry plants and medical herbs growing in the Shatsk National Natural Park (Volyn Region, Ukraine). It is shown that the 137 Cs content for most of the medical herbs has significantly decreased during the monitoring time period and now it meets the demands of Ukrainian sanitary standards (less than 200 Bq/kg d. w.). The decreasing rate is much higher than that for the corresponding soils. This is because the radionuclide available in the soil becomes less accessible for digesting by the plant rootage in the course of time. The 137 Cs content in the vegetative and generative organs of bilberry shows essential seasonal variations. The corresponding content for the foliage reveals almost double decrease during the period when the berries ripen and an increase occurring after fructification.

Dynamic bayesian modelling for radionuclide soil-to-plant transfer

“…• Need for K+, 2 Ca+ and other cations 137 Cs and 90 Sr are not the only radionuclides left in soils after Chornobyl disaster, yet being the most dangerous. The major danger is caused by their feature of substituting the vital minerals: 137 Cs is perceived as K, and 90 Sr as 2 Ca. The plants literally mistake the radionuclides for these cations and get contaminated.…”

“…K+ and 2 Ca+ are antagonist ions for 137 Cs and 90 Sr respectively. The higher is the demand of the plant in K+ and 2 Ca+, the higher is the absorption of 137 Cs and 90 Sr.…”

“…28 years after, the problem of soil re-cultivation gains higher and higher importance, because a particular dynamic balance in radionuclide migration processes has been established. This allows researchers to predict that in the following decades this stability will not change at the high grade [2]. The main risk factor lays in the fact that agricultural products, obtained from re-cultivated territories, has to be compliant with the quality standards and to be safe for human life and health.…”