Volume 1, Issue 3 (December 2016)

Original research papers



Miryana Varbeva, Petya Kovacheva

Pages: 204-209

DOI: 10.21175/RadJ.2016.03.038

Received: 29 FEB 2016, Received revised: 22 APR 2016, Accepted: 30 APR 2016, Published online: 26 DEC 2016

Rapid changes of the environmental temperature can alter soil characteristics and influence the migration ability and bioavailability of the radionuclides. Elucidation of the effects of extreme weather conditions on the transfer factors of radionuclides in different soil types is especially important for adequate risk assessment after radioactive contamination. This paper presents the impact of a rapid increase of environmental temperature for a period of one month on the bioaccumulation of 60Co, 137Cs and 54Mn from three soil types to orchard grass. The experiment was performed by soil samples, taken from the surface soil layer 0-10 cm of Albic cambisol, Calcaric chernozem and Gleyic fluvisol soils (classified according to World Reference Base for Soil Resources/FAO) from Bulgaria. The samples were contaminated by a radioactive solution of 60Co, 137Cs and 54Mn, separated into two subsamples and stored during one month at two temperature regimes: 15 оС and 40 оС by using of a climate chamber. Afterwards, the soils were planted with orchard grass and stored at 15 oC during two weeks until growing and the transfer factors were determined. The results showed that rapid warming during one month after radioactive contamination caused a decrease of the transfer of 137Cs from all studied soils to orchard grass. The decrease of the transfer factors of 60Co and 54Mn from the soil with high cation-exchange capacity, higher quartz and muscovite content was determined, while the increase of the transfer factors of 60Co and 54Mn from the soil with very low cation-exchange capacity and lower content of quartz and micaceous minerals was registered. Prognostic maximum specific activities of the radionuclides in the investigated soils, at which milk and meat are harmless to be consumed, were calculated referring to the obtained data.
  1. M. Dowdall, W. Standring, G. Shaw and P. Strand, “Will global warming affect soil-to-plant transfer of radionuclides?” J. Environ. Monit., vol. 99, pp. 1736–1745, 2008.
    DOI: 10.1016/j.jenvrad.2008.06.012
  2. P. Kovacheva, D. Yovkova, B. Todorov and R. Djingova, “Effects of freezing and soil drought on the geochemical fractionation of americium in Fluvisol and Cambisol soils from Bulgaria,” Centr. Eur. Geol., vol. 56, no. 1, pp. 1-12, 2013.
    DOI: 10.1556/CEuGeol.56.2013.1.1
  3. P. Kovacheva, S. Mitsiev and R. Djingova, “Physicochemical fractionation of Americium, Thorium and Uranium in Chernozem soil after sharp temperature change and soil drought,” Chem. Pap., vol. 68, no. 3, pp. 336-341, 2014.
    DOI: 10.2478/s11696-013-0457-y
  4. P. Kovacheva and R. Djingova, “Influence of freezing on the physicochemical forms of natural and technogenic radionuclides in Chernozem soil,” Chem. Pap., vol. 68, no. 5, pp. 714-718, 2014.
    DOI: 10.2478/s11696-013-0483-9
  5. P. Kovacheva, M. Slaveikova, B. Todorov and R. Djingova, “Influence of temperature decrease and soil drought on the geochemical fractionation of 60Co and 137Cs in fluvisol and cambisol soils,” Appl. Geochem., vol. 50, pp. 74-81, 2014.
    DOI: 10.1016/j.apgeochem.2014.08.010
  6. International Atomic Energy Agency. (Vienna, 2006) IAEA-TECDOC-1497, Classification of soil systems on the basis of transfer factors on radionuclides from soil to reference plants, p. 250.
  7. International Atomic Energy Agency. (Vienna, 2010.) Technical reports series No. 472, Handbook of parameter values for the prediction of radionuclide transfer in terrestrial and freshwater environments, p. 194.
  8. P. Kovacheva, B. Todorov and R. Djingova, “Geochemical fractionation and bioavailability of 241Am, 60Co and 137Cs in Fluvisol soil after sharp temperature variation before the growing season,” Centr. Eur. Geol., vol. 57, no. 2, pp. 151-161, 2014.
    DOI: 10.1556/CEuGeol.57.2014.2.3
  9. Food and Agriculture Organization of the United Nations. (Rome, 2006). World Soil Resources Report 103, World Reference Base for Soil Resources. A Framework for International Classification Correlation and Communication, p. 128
  10. Bulgarian food safety agency, Preliminary information on the radioactive contamination and the measures undertaken by the EC countries and Bulgaria regarding the foods after the accident in the nuclear power plant in Fukushima, Japan, Bulgaria, 2011 (in Bulg.)
  11. M. Roig, M. Vidal, G. Rauret and A. Rigol, “Prediction of radionuclide aging in soils from the Chernobyl and Mediterranean area,” J. Environ. Qual., vol.36, pp. 943-952, 2007.
    DOI: 10.2134/jeq2006.0402
  12. A. Manceau, M. Schlegel, K. L. Nagy, and L. Charlet, “Evidence for the formation of trioctahedral clay upon sorption of Co2+ on quartz,” J. Colloid Interface Sci., vol. 220, no. 2, pp. 181-197, 1999.
    DOI: 10.1006/jcis.1999.6547
  13. N. K. Ishikawa, S. Uchida and K. Tagami, “Radiocesium sorption behavior on illite, kaolinite, and their mixtures,” Radioprotection, vol. 44, no. 5, pp. 141-145, 2009.
    DOI: 10.1051/radiopro/20095030