Relationship between concentration of rare earth elements in soil and their distribution in plants growing near a frequented road

Abstract

Rare earth elements (REEs) are a group of elements whose concentration in numerous environmental matrices continues to increase; therefore, the use of biological methods for their removal from soil would seem to be a safe and reasonable approach. The aim of this study was to estimate the phytoextraction efficiency and distribution of light and heavy (LREEs and HREEs) rare earth elements by three herbaceous plant species: Artemisia vulgaris L., Taraxacum officinale F.H. Wigg. and Trifolium repens L., growing at a distance of 1, 10, and 25 m from the edge of a frequented road in Poland. The concentration of REEs in soil and plants was highly correlated (r > 0.9300), which indicates the high potential of the studied plant species to phytoextraction of these elements. The largest proportion of REEs was from the group of LREEs, whereas HREEs comprised only an inconsiderable portion of the REEs group. The dominant elements in the group of LREEs were Nd and Ce, while Er was dominant in the HREEs group. Differences in the amounts of these elements influenced the total concentration of LREEs, HREEs, and finally REEs and their quantities which decreased with distance from the road. According to the Friedman rank sum test, significant differences in REEs concentration, mainly between A. vulgaris L., and T. repens L. were observed for plants growing at all three distances from the road. The same relation between A. vulgaris L. and T. officinale was observed. The efficiency of LREEs and REEs phytoextraction in the whole biomass of plants growing at all distances from the road was A. vulgaris L. > T. officinale L. > T. repens L. For HREEs, the same relationship was recorded only for plants growing at the distance 1 m from the road. Bioconcentration factor (BCF) values for LREEs and HREEs were respectively higher and lower than 1 for all studied plant species regardless of the distance from the road. The studied herbaceous plant species were able to effectively phytoextract LREEs only (BCF > 1); therefore, these plants, which are commonly present near roads, could be a useful tool for removing this group of REEs from contaminated soil.

Phytoaccumulation of heavy metals in native plants growing on soils in the Spreča river valley, Bosnia and Herzegovina

“…In the present study, the highest bioaccumulation of Cr and Ni was noticed in Trifolium repens L. and Artemisia vulgaris L. Earlier studies also revealed that Trifolium repens L. and Artemisia vulgaris L. could accumulate Ni and Cr effectively (Mleczek et al 2018, Lin et al 2021. Furthermore, both plant species have the ability to adapt to different environments, produce high biomass and offer multiple harvests in a single growth period.…”

Fractionation and Distribution of Rare Earth Elements in Marine Sediment and Bioavailability in Avicennia marina in Central Red Sea Mangrove Ecosystems

“…The amount of bioavailable REE could also form the primary reason for the significant variation in REE concentration in mangrove leaves across the six mangrove ecosystems, even though the mangroves are of the same species. Several studies have also revealed that REE phytoextraction increases with an increase in sediment concentration of REE, and differences in the environment, either due to anthropogenic activities or chemical weathering, might influence sequestration of REE [ 43 , 44 , 45 ].…”

Rare Earth Elements and Bioavailability in Northern and Southern Central Red Sea Mangroves, Saudi Arabia

“…The major reason for the substantial dissimilarity in REE composition in A. marina leaves could be due to the bioavailable REE content in the two mangroves investigated. Previous studies have established a positive correlation between increased REE phytoextraction, the concentration of REE in sediment, and environmental variations due to anthropogenic influence or weathering of chemical nature, with the tendency of affecting REE sequestration [ 19 , 49 ].…”