Date of Award
Spring 5-10-2018
Degree Type
Thesis
Degree Name
Master of Science in Integrative Biology (MSIB)
Department
Biology
Committee Chair/First Advisor
Dr. Christopher Dockery
Major Professor
Dr. Daniel Ferreira
Second Committee Member
Dr. Matthew Weand
Abstract
An earthquake in Japan led to the meltdown of the Fukushima Daiichi Nuclear Power Plant which released radionuclides into the surrounding regions. Of these radionuclides, cesium-137 (137Cs+) has been shown to be the most abundant. Research has shown that adsorption of K+ and Cs+ on 2:1 clay minerals can collapse the interlayers, causing the adsorbed ion to become non-exchangeable. This thesis takes an integrative approach to the restoration of radiocesium-contaminated soil in three parts by 1) evaluating the adsorption behavior and mechanisms of Cs+ in vermiculite, 2) using plants as bioindicators to elucidate long-term radiation exposure and testing the bioindicators as possible sources of phytoremediation, and 3) experimenting with a Cs+-capturing ligand to develop a chemical extraction method that can be used to restore contaminated soil in Fukushima Prefecture. Results have shown a strong adsorption mechanism exhibited by Cs+ to vermiculite services with no true interlayer collapse. The bioindicators species did not reveal any morphological characteristics that could attributed to radiocesium uptake and are being evaluated for total radiocesium concentration in their tissue. The chemical extraction results indicate that radiocesium can be removed more efficiently when the clay fraction is properly extracted and isolated from Fukushima Prefecture soils. It is the intent of this thesis to provide information that can be used to advance the scientific community’s ability to improve Fukushima Prefecture’s soil more quickly.