Löfgren, Stefan
- Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences
Abstract
The plant-available pools of calcium, magnesium and potassium are assumed to be stored in the soilas exchangeable cations adsorbed on the cation exchange complex. In numerous forest ecosystems,despite very low plant-available pools, elevated forest productivities are sustained. We hypothesizethat trees access nutrient sources in the soil that are currently unaccounted by conventional soilanalysis methods. We carried out an isotopic dilution assay to quantify the plant-available poolsof calcium, magnesium and potassium and trace the soil phases that support these pools in 143individual soil samples covering 3 climatic zones and 5 different soil types. For 81%, 87% and 90%of the soil samples (respectively for Ca, Mg and K), the plant-available pools measured by isotopicdilution were greater than the conventional exchangeable pool. This additional pool is most likelysupported by secondary non-crystalline mineral phases in interaction with soil organic matter andrepresents in many cases (respectively 43%, 27% and 47% of the soil samples) a substantial amount ofplant-available nutrient cations (50% greater than the conventional exchangeable pools) that is likelyto play an essential role in the biogeochemical functioning of forest ecosystems, in particular when theresources of Ca, Mg and K are low.
Published in
Scientific Reports
2020, volume: 10, number: 1, article number: 15703
SLU Authors
Associated SLU-program
Acidification
Global goals (SDG)
UKÄ Subject classification
Geochemistry
Soil Science
Environmental Sciences
Publication identifier
- DOI: https://doi.org/10.1038/s41598-020-72741-w
Permanent link to this page (URI)
https://res.slu.se/id/publ/108816