Coupling metal stable isotope compositions and X-ray absorption spectroscopy to study metal pathways in soil-plant systems: a mini review

Excess and limited trace metal contents in soils and plants can limit crop yields and pose a risk for the environment and human health. This mini-review reports on the emerging approach of combining X-ray absorption spectroscopy (XAS) with isotope analyses to improve the understanding of metal speciation and dynamics in soil-plant systems. In soils and their components, shifts in isotope compositions could be in some cases linked to changing metal speciation and thereby provide information on processes that control the phytoavailability of metals. In plants, the XAS-isotope approach has potential to improve the understanding of how complex interactions of metal speciation, redox processes, and membrane transport control metal uptake and translocation to edible plant parts. Yet, the XAS-isotope approach proves to be in a rather exploratory phase, and many research gaps remain. Such limitations can be overcome by methodological improvements and combining the approach with molecular biology and modelling approaches.

Automated summary

Excess and limited trace metals in soils and plants can hinder crop yields and pose risks to the environment and human health. The combination of X-ray absorption spectroscopy (XAS) with isotope analyses is an emerging approach that can improve understanding of metal speciation and dynamics in soil-plant systems. This approach shows promise in providing insights into metal availability in soils and metal uptake and translocation in plants, although further research and methodological advancements are needed.