Comparison of 226Ra nuclide from soil by three woody species Betula pendula, Sambucus nigra and Alnus glutinosa during the vegetation period.

The uptake of 226Ra from the contaminated soil was compared in three woody species: alder (Alnus glutinosa), birch (Betula pendula) and elder (Sambucus nigra). The 226Ra activities increased during the vegetation periods (in 2003, 2004 and 2005) both in the leaves and flowers+seeds. The highest accumulation was found in birch, reaching 0.41 Bq/g DW in the leaves (at the end of the vegetation period in 2003). The lowest 226Ra accumulation was determined in alder. The extent of 226Ra accumulation in the leaves of woody species demonstrates that these pioneer woody species can be used as remediation alternative to the use of herbs, provided that the removal of fallen leaves could be achieved in the end of vegetation period.