Journalartikel

Jahr der Veröffentlichung: 2000

Seiten: 197-202

Zeitschrift: Journal of Plant Nutrition and Soil Science

Bandnummer: 163

Heftnummer: 2

ISSN: 1436-8730

eISSN: 1522-2624

Verlag: Wiley-VCH Verlag

Abstract: 
Cadmium (Cd) sorption isotherms were estimated by two different analytical approaches to assess the influence of initial Cd concentrations of soil matrix on the sorption of added Cd. For the laboratory experiments a heterogeneous set of samples was collected to include a wide range of different initial Cd concentrations. Comparison of both analytical methods (conventional analysis, radioanalysis) resulted in a strong conformity of Cd contents in solution at equilibrium. The calculated Cd concentrations in the soil solid phase differ according to the analytical approach for considering the initial contents. The determination of the initial contents by the proposed radioanalytical method with Cd-109 resulted in long linear Freundlich-isotherms, even in the low concentration range. Thus, radioanalysis seems to be me most suitable method to recognise the initial contents of Cd in soil. EDTA extractable Cd represent the initial concentrations, which are averaged over solid and liquid phase. However, depending on the sorption characteristics of the soil these rates vary. In the investigated set of soil samples 52.3 to 99.3% of Cd must be added to the solid phase.