Uptake of some radionuclides by woody plants growing in the rainforest of Western Ghats in India

Transfer of the naturally occurring radionuclides U-238, Th-232 in and K-40, and the fallout radionuclide Po-210 to different wild plant species in the rainforest of Western Ghats was analyzed. A number of physiologically different plants from the top storey and understorey, such as shrubs and epiphytes, were compared. The concentrations of these radionuclides in the plants and soil were measured using a gamma ray spectrometer and an alpha counter, and were found to vary widely within plants and between species. The soil-plant ratios also varied between species while Elaeocarpus oblongus and epiphytic plants exhibited preferential uptake of these radionuclides. As a result, the dust particles trapped in the root systems of epiphytes could be used as bioindicators of fallout radionuclides in the Western Ghats. (C) 2014 Elsevier Ltd. All rights reserved.