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In recent years, radioactive contamination in the environment by uranium (U) and its daughters has caused increasing concerns globally. This book provides recent developments and comprehensive knowledge to the researchers and academicians who are working on uranium contaminated areas worldwide. This book covers topics ranging from the beginning of the nuclear age until today, including historical views and epidemiological studies. Modelling practices and evaluation of radiological and chemical impact of uranium on man and the environment are included. Also covered are analytical methods used for the determination of uranium in geo/bio environments. Some chapters explore factors which influence uranium speciation and in consequence plant uptake/translocation. Last but not least, several chapters provide approaches and practices for remediation of uranium contaminated areas.

This book provides extensive and comprehensive knowledge to the researchers/academics who are working in the field of cesium contaminated sites, and the impact on plants. This book is also helpful for graduate and undergraduate students who are specializing in radioecology or safe disposal of radioactive waste, remediation of legacies and the impact on the environment. Radiocesium (137Cs and 134Cs) was released into the environment as a result of nuclear weapons testing in 1950s and 1960s (~1x1018 Bq), and later due to the Chernobyl accident in 1986 (8.5x1016 Bq) and Fukushima Daiichi Nuclear Power Plant in 2011 (~1x1017 Bq). 137Cs is still of relevance due to its half-life of 30 years. The study of radioisotope 137Cs is important, as production and emission rates are high compared to other radioisotopes, due to high fission yield and high volatility.This book contains original work and reviews on how cesium is released into the environment on translocation from soil to plants and further on to animals and into the human food chain. Separate chapters focus on the effective half-life of cesium in plants and on how different cultivars are responding in accumulation of cesium. Other key chapters focus on cesium impact on single cells to higher plants and also on remediation measures as well as on basic mechanism used for remedial options and analysis of transfer factors. The book rounds off by contributions on cesium uptake and translocation and its toxicity in plants after the Chernobyl and Fukushima accidents.

This book reports the results from on-site research into radioactive cesium contamination in various agricultural systems affected by the Fukushima Daiichi Nuclear Power Plant accident that occurred in March 2011. This is the second volume from the research groups formed in the Graduate School of Agricultural and Life Sciences of The University of Tokyo who have published the initial data in their first volume. In this book, additional data collected in the subsequent years are presented to show how the radioactivity level in agricultural products and their growing environments have changed with time. The data clarify the route by which radioactive materials entered agricultural products and their movement among different components (e.g., soil, water, and trees) within an environmental system (e.g., forests). The book consists of various topics, including radioactivity inspection of food products; decontamination trials for rice and livestock production; the state of contaminationin wild animals and birds, trees, mushrooms, and timber; the dynamics of radioactivity distribution in mountain and paddy fields; damage incurred by the forestry and fishery industries; and the change in consumers'minds. The last chapter introduces a real-time radioisotope imaging system, the forefront technique to visualize actual movement of cesium in soil and in plants. This is the only book to provide systematic data about the actual change of radioactivity, and thus is of great value for all researchers who wish to understand the effect of radioactive fallout on agriculture. The project is ongoing; the research groups continue their work in the field for further evaluation of the long-term effects.

This book provides extensive and comprehensive information to researchers and academicians who are interested in radionuclide contamination, its sources and environmental impact. It is also useful for graduate and undergraduate students specializing in radioactive-waste disposal and its impact on natural as well as manmade environments.A number of sites are affected by large legacies of waste from the mining and processing of radioactive minerals. Over recent decades, several hundred radioactive isotopes (radioisotopes) of natural elements have been produced artificially, including 90Sr, 137Cs and 131I. Several other anthropogenic radioactive elements have also been produced in large quantities, for example technetium, neptunium, plutonium and americium, although plutonium does occur naturally in trace amounts in uranium ores. The deposition of radionuclides on vegetation and soil, as well as the uptake from polluted aquifers (root uptake or irrigation) are the initial point for their transfer into the terrestrial environment and into food chains. There are two principal deposition processes for the removal of pollutants from the atmosphere: dry deposition is the direct transfer through absorption of gases and particles by natural surfaces, such as vegetation, whereas showery or wet deposition is the transport of a substance from the atmosphere to the ground by snow, hail or rain. Once deposited on any vegetation, radionuclides are removed from plants by the airstream and rain, either through percolation or by cuticular scratch. The increase in biomass during plant growth does not cause a loss of activity, but it does lead to a decrease in activity concentration due to effective dilution. There is also systemic transport (translocation) of radionuclides within the plant subsequent to foliar uptake, leading the transfer of chemical components to other parts of the plant that have not been contaminated directly.

Following the Fukushima nuclear accident, a large volume of monitoring data has been collected about the soil, air, dust, and seawater, along with data about an immense number of foods supplied to the market. Little is known, however, about the effect of radioactive fallout on agriculture, information about which is vital. Although more than 80% of the damaged area is related to agriculture, in situ information specifically for agriculture is scarce. This book provides data about the actual movement and accumulation of radioactivity in the ecological system—for example, whether debris deposited on mountains can be a cause of secondary contamination, under what conditions plants accumulate radioactive cesium in their edible parts, and how radioactivity is transferred from hay to milk. Because agriculture is so closely related to nature, many specialists with different areas of expertise must be involved in answering these questions. In the case of rice, researchers in rice cultivation as well as in soil, hydrology, and radioactivity measurement are working together to reveal the paths or accumulation of radioactivity in the field. For this purpose, the Graduate School of Agricultural and Life Sciences of The University of Tokyo has diverse facilities available throughout Japan, including farmlands, forests, and meadowlands. Many academic staff members have formed groups to conduct on-site research, with more than 40 volunteers participating. This book presents the data collected from the only project being systematically carried out across Japan after the Fukushima accident.