Interaction between soil water saturation and toxic element accumulation in woody plants (Freiberg region, Germany)

ABSTRACT

Relationships between soil water saturation (SWS) and the accumulation of arsenic (As), cadmium (Cd), and lead (Pb) in soils and aboveground biomass of Populus tremula and Salix caprea were explored. SWS was computed with the hydrological model ParFlow/CLM and compared to data from field observations. Plant and soil samples collected at the main pollution sources contained the highest concentrations of As, Cd, and Pb. S. caprea contained higher concentrations of As, Cd, and Pb than P. tremula. In both species, metal(loid) concentrations in leaves were significantly higher than in branches. At strongly mining-affected locations, metalloid concentration in the trees largely reflected the pollution levels in the soil. In remote study locations, the soil–plant transfer of Cd and Pb was affected by water saturation: element accumulation increased significantly with soil moisture. Results demonstrate that coupling field observations with hydrological modelling is a promising approach for estimating element accumulation.

KEYWORDS:

• Soil moisture
• bio-accumulation
• Salix caprea
• Populus tremula
• heavy metals

Acknowledgments

VL was funded by a research fellowship granted by the DAAD and the Helmholtz Association of German Research Centres in Forschungszentrum, Juelich. We gratefully acknowledge the Earth System Modelling Project (ESM) for funding the part of SWS by providing computing time on the ESM partition of the supercomputer JUWELS at Jülich Supercomputing Centre (JSC).

Disclosure statement

No potential conflict of interest was reported by the author(s).