Schwermetall-Verarmung in der Rhizosphäre verschiedener Kulturpflanzen — Erste Ergebnisse

Abstract

New designed “rhizoboxes„, where plants are grown for three weeks, are used to get 1 mm thin sections of rhizosphere soil. Soil samples are extracted with different solutions in order to assess the mobility and the binding forms of heavy metals dependent on the distance from the plant roots.

A depletion of heavy metals in the rhizosphere is detectable; the extent depends on the kind of metal (Pb, Cd,, Cu, Zn), plant species and soil characteristics. Compared to the total supply of heavy metals in the soils, the amount taken up by the plants is very low. Therefore, mild extractants (e.g. water or NH₄NO₃) are more suitable to indicate a decrease of heavy metals near the roots than agents extracting the total amount or large proportions of it.