Uptake of uranium, thorium, radium and potassium by four kinds of dominant plants grown in uranium mill tailing soils from the southern part of China

Abstract

The concentrations of radionuclides in soil from uranium mill tailings in South China were analyzed. The results showed that all radionuclides in soil samples exceeded the soil background value. Through the field investigation, four kinds of dominant plants were identified. It was found that the total quantity of radionuclides in the whole plant from high to low were pokeberry, Cibotium barometz, reed and garden sorrel. We also found that Cibotium barometz had the highest transfer factor (TF) for 238 U, garden sorrel had the highest TF for 232 Th and reed had the highest TF for 226 Ra and 40 K. Cibotium barometz had the highest bioconcentration factor (BF) for 238 U, 232 Th and 226 Ra, and pokeberry had the highest BF for 40 K. Pokeberry had the highest phytoremediation factor (PF) for 238 U, 232 Th, 226 Ra and 40 K. On the basis of the above conclusions, pokeberry could be a candidate for phytoremediation of radionuclide-contaminated soils.

Substratum influences uptake of radium-226 by plants

“…Several studies have focused on the uptake of 226 Ra by plants, quantifying a transfer factor (or concentration ratio) of 226 Ra from the soil to the plant tissues (Simon and Ibrahim, 1990;Sheppard et al, 2006;Vandenhove et al, 2009;Uchida et al, 2009). Predominantly, because of the need to assess the radium content of agricultural products and the risk to the population, researches on the 226 Ra uptake by plants have been carried out in 226 Ra-contaminated areas (e.g., Simon and Ibrahim, 1990 and references herein), such as former or operating uranium mining and milling sites (Marple, 1980;Vasconcellos et al, 1987;Bettencourt et al, 1988;Ibrahim and Whicker, 1992; SUBSTRATUM INFLUENCES RADIUM-226 UPTAKE BY PLANTS 6 Markose et al, 1993;Madruga et al, 2001;Blanco Rodríguez et al, 2002Vera Tomé et al, 2002;Chen et al, 2005;Ryan et al, 2005;Soudek et al, 2007aSoudek et al, ,b, 2010Carvalho et al, 2009;Černe et al, 2011;Medley et al, 2013;Hu et al, 2014;Medley and Bollhöfer, 2016;Yan and Luo, 2016), phosphate fertilizer processing complexes (Paul and Pillai, 1986;Martínez-Aguirre and Periáñez, 1998), radium salt factories (Bettencourt et al, 1988), depleted uranium ammunition sites (Popovic et al, 2008), and other industrial units (Paul and Pillai, 1986). These studies have been complemented by experiments on artificially 226 Ra-enhanced soils at the laboratory scale in pots or at larger scale in lysimeter and field experiments …”

Enhancement of Uranium Recycling from Tailings Caused by the Microwave Irradiation-Induced Composite Oxidation of the Fe–Mn Binary System

“…However, the segregation technique makes the accumulation and further infiltration of radionuclides easier during long-term weathering processes. , The recent progress in biohydrometallurgy for mining has been reported in several reviews . More other enhancements are necessarily put forward for the microbe-related activities to overcome the inapplicability of biohydrometallurgy to the refractory U tailings. , The phytoremediation method utilizes some plants to effectively adsorb radionuclides from contaminated aquifers or soils, reducing the migration and diffusion of radionuclides on the surfaces. − However, the contaminated plants need real-time monitoring and timing harvesting and postdisposal. Some radionuclides can be rashly brought into the biosphere through the intermediary role of some plants.…”