Biogeochemistry and pedogeochemistry of the White Spur area, near Rosebery, Tasmania

Abstract

A comparative study of element distribution in soils and plants was conducted over an area in western Tasmania. Analyses of the trees indicated that in general Cu, Pb, Zn, Fe, Ni, Ba, and Cd are preferentially concentrated in the wood, followed in order by the bark, old and young twigs, and finally the leaves. Manganese is preferentially concentrated in the bark followed by the leaves, twigs, and wood. Of the five plant organs sampled, only the leaves proved to be of any use in reflecting the Pb, Fe, and Mn soil concentrations. Reflection for Cu, Zn, and Ni is poor. Chemical analyses of decayed organic material in the top soil correlate well with soil and bedrock concentrations. The downslope soil geochemical dispersion pattern is similar to a chromatogram: iron precipitates first where ground water surfaces, followed by manganese, and later, lead precipitation. Zinc travels farther, and copper and nickel generally escape the system. Vertical distribution in the soils shows the same relative elemental mobilities.