Workman, Daniel, authorJohnson, Thomas, advisorSudowe, Ralf, committee memberOmur-Ozbek, Pinar, committee member2019-01-072019-01-072018https://hdl.handle.net/10217/193194The objective of this research was to investigate the activity of radiocesium in plants and soil found in forested areas near the Fukushima Dai-Ichii Nuclear Power Station (FDNPS). Plant samples and 15-cm soil core samples were collected at four sampling locations. The quantity of soluble and exchangeable amounts of 137Cs in soil was measured by performance of two sequential extractions using de-ionized water and ammonium acetate respectively. The remaining radiocesium bound to the soil following the extractions was considered strongly bound to soil particles and whose movement into either soluble or exchangeable concentrations is slow. The distribution of the different forms of radiocesium were developed throughout each 15-cm soil core as measured using a High Purity Germanium Detector (HPGe). An analysis of correlation between plant activity versus plant root area and exchangeable radiocesium resulted in limited success. It remains probable that quantifying plant root radiocesium distribution can aid in predicting plant uptake, but it is believed that the concentrations of competing ions in soil should also be quantified and parameterized as well as additional possible routes of intake (throughfall). Concentration ratios (137Cs plant activity/137Cs soil activity) of 12 plants were calculated and exhibited a broad range from 0.01 to 2.5. The broad range of plant concentration falls within the International Atomic Energy Agency Parameter Handbook values of herbaceous plants in clay soils. Concentration ratios appear similar within sampling locations which suggests that additional soil characteristics (clay content, competing ions) can be used to describe plant uptake of radiocesium.born digitalmasters thesesengCopyright and other restrictions may apply. User is responsible for compliance with all applicable laws. For information about copyright law, please see https://libguides.colostate.edu/copyright.Text