Soil chemical extractions are widely used to predict the nutritional status of soils. However, the correlation between extracted elements and plant uptake is often poor, especially if compared over a range of soil types. The aim of this study was to examine a new method called Diffusive Gradients in Thin films (DGT), which measures the diffusive supply of elements, thereby mimicking a plant root. The ability of DGT to assess plant-available P, Zn and Cu was tested in a wide range of typical Scandinavian agricultural soils along with conventional methods (EDTA and DTPA for Cu and Zn; NaHCO 3 for P and soil solution concentrations). Extracted soil concentrations were compared to that of the element in the youngest fully developed leaf of barley (Hordeum vulgare L.) grown in pots. For Zn and P, only DGT could predict plant uptake while conventional extraction methods and soil solution analyses performed poorly. All soil tests could predict Cu concentration in leaves, but the DGT technique proved to be most accurate followed by the soil solution concentration of Cu. We conclude that DGT is much more accurate at predicting plant-available P, Zn and Cu than commonly used methods for analysing plantavailable nutrients in soil.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.