Geographical and vertical distribution of radiocesium levels in coniferous forest soils in Izmir

Preliminary picture of 137Cs radioactivity levels in forested areas in and around Izmir is illustrated. Both activity concentrations and activity depositions of 137Cs in soil samples were determined. Their values varied from 8.29±0.27 to 445±3.16 Bq x kg-1 (d.w.) and 0.63±0.01 to 11.6±0.08 kBq x m-2 (d.w.), respectively. It was found that while activity deposition of 137Cs is normally distributed, activity concentration of 137Cs is log-normally distributed in forest soils and the activity deposition is less variable than the activity concentration. Cesium-137 activities in soils increase with increasing elevation, annual average rainfall and soil organic matter. (author)