Screening of Plant Species for Phytoremediation of Uranium, Thorium, Barium, Nickel, Strontium and Lead Contaminated Soils from a Uranium Mill Tailings Repository in South China

Abstract

The concentrations of uranium, thorium, barium, nickel, strontium and lead in the samples of the tailings and plant species collected from a uranium mill tailings repository in South China were analyzed. Then, the removal capability of a plant for a target element was assessed. It was found that Phragmites australis had the greatest removal capabilities for uranium (820 μg), thorium (103 μg) and lead (1,870 μg). Miscanthus floridulus had the greatest removal capabilities for barium (3,730 μg) and nickel (667 μg), and Parthenocissus quinquefolia had the greatest removal capability for strontium (3,920 μg). In this study, a novel coefficient, termed as phytoremediation factor (PF), was proposed, for the first time, to assess the potential of a plant to be used in phytoremediation of a target element contaminated soil. Phragmites australis has the highest PFs for uranium (16.6), thorium (8.68), barium (10.0) and lead (10.5). Miscanthus floridulus has the highest PF for Ni (25.0). Broussonetia papyrifera and Parthenocissus quinquefolia have the relatively high PFs for strontium (28.1 and 25.4, respectively). On the basis of the definition for a hyperaccumulator, only Cyperus iria and Parthenocissus quinquefolia satisfied the criteria for hyperaccumulator of uranium (36.4 μg/g) and strontium (190 μg/g), and could be the candidates for phytoremediation of uranium and strontium contaminated soils. The results show that the PF has advantage over the hyperaccumulator in reflecting the removal capabilities of a plant for a target element, and is more adequate for assessing the potential of a plant to be used in phytoremediation than conventional method.

Simulation Model for Feasibility Studies on Bioremediation of Uranium Mill Tailings using Hyper Accumulator <i>Chrysopogon zizanioides</i>

“…Previous studies by (Li et al, 2011) has indicated that the removal efficiency of bean plants was higher when exposed to lower concentrations of uranium compared to higher concentration and the time required to attain the same removal efficiency of uranium was longer. Shahandeh and Hossner (2002) have stated that the uranium uptake by the plant is affected by the pH, iron and manganese oxides and the texture of the soil (Shahandeh and Hossner, 2002).…”

“…A comparison of the previous work on phytoremediation of uranium either in the field or lab conditions showed that vetiver has a moderate phytoremediation effect compared to other plants like Helianthus annuus, Cyperus iria, Parthenocissus quinquefolia, Panicum maximum, Juncellus serotinus, Brassica junceaand Phragmites australis (Li et al, 2011), (Shahandeh and Hossner, 2002), (Roongtanakiat et al, 2010). Similar to our simulation studies in the tanks; in these reports; the analysis were carried out for a maximum period of 90 days, but the work was performed either under laboratory conditions, or samples were taken only once.…”

Phytoremediation of Radionuclides: A Report on the State of the Art

“…Members of family Brassicace, Thlaspi caerulescens and Amaranth retroflexus are found as hyperaccumulators of Co and Sr (McCutcheon and Schnoor 2003). Li et al (2011) performed studies for the analysis of concentrations of U, Th, Ba, Ni, Sr and Pb in plant species collected from uranium mill tailings. The removal capability of a plant for a target element was assessed.…”

An artificially constructed Syngonium podophyllum-Aspergillus niger combinate system for removal of uranium from wastewater

“…The content of uranium in the plants was measured in the following procedures. Two grams of the plant sample was taken and was put into the oven to dry at 105°C for 24 h (Li et al 2011). The sample was digested using the method by Hu et al (2012).…”