Abstract
In order to evaluate the effect of different land use on lithogenic Tl geochemistry, two forest and grassland soils developed on an identical Tl-rich substrate were examined. The modified BCR sequential extraction combined with X-ray diffraction analysis (XRD) and voltammetry of microparticles (VMP) were performed for a detailed insight on lithogenic Tl speciation and availability in both contrasting soils.
It was revealed that soil forming processes like bioturbation and probably dust deposition may influence the increased input of lithogenic Tl into the forest floor. Thallium was predominantly bound within the residual fraction (up to 95%) corresponding to primary silicates (mainly orthoclase and muscovite) and probably secondary illite.
The highest portion (~ 5%) of “labile” Tl was found in the organic horizons of the forest soil. Thallium adsorption was dominated by an identified non-cry