Sorption of 137Cs from undisturbed forest soil in a zeolite trap

A method to study the time-integrated migration of radiocaesium (137Cs) from undisturbed coniferous forest soil cores is presented, which is based on a natural zeolite trap enclosed in a semi-permeable membrane that can be mounted into soil cores. Results show that higher zeolite trapping of 137Cs occurred in a forest soil with high soil-plant transfer parameters, low pH and high organic contents. Part of the biologically bound 137Cs that was associated within the soil microflora and microfauna appears to increase the migration of 137Cs after heating of the soil cores. Therefore, migration and mobility of 137Cs in forest soil seems to depend to a major extent upon the soilʹs physical and chemical parameters, particularly the activity concentration of 137Cs in soil solution, soil pH, percentage of soil organic matter (OM%) and soil mineral type.