Vanadium fractionation by the BCR procedure from arable soils of the Siedlce upland region / Wanad we frakcjach wydzielonych metodą BCR w glebach uprawnych wysoczyzny siedleckiej

The content of vanadium in exchangeable (F1), reducible (F2), oxidisable (F3) and residual fractions (F4) separated by BCR sequential extraction procedure and their distribution in 11 arable profiles of Eutric Cambisols, Haplic Luvisols and Stagnic Luvisols located on the Siedlce upland was evaluated. In these soils, the varied natural, not contaminated levels of total vanadium content were determined. Chemical analyses revealed that mean contents of vanadium in separated fractions, independently of type of investigated soils, can be arranged in the following decreasing series: F4 > F2 > F3 > F1. The highest amounts of this element in F1 (1.7%) and F4 (83.3%) fractions – in Stagnic Luvisols, and F2 (13.0%) and F3 (7.0%) fraction – in Eutric Cambisols were determined. The highest vanadium percentage share in the F1, F2 and F3 fractions was measured in the humus horizon (Ap) and in the F4 – in the enrichment horizons (B) and parent material horizons (Ck). A statistical analysis revealed the significant impact of selected soil properties (pH, Fe, Al and Mn compounds, CEC, Corg, clay fraction ø < 0.002 mm) on vanadium fractionation in investigated soils.