Bioindication of heavy metals in soil by liverworts.

Abstract

Studies were made of the accumulation of the heavy metals Ba, Cd, Co, Cr, Cu, Fe, Hg, Ni, Pb, Sr, V, and Zn and the macroelements N, P, K, Ca, and Mg in liverworts Conocephalum conicum, Marchantia polymorphia, and Pellia epiphylla collected from 57 microhabitats in Poland (Lower Silesia, Tatry Mts., and Puszcza Augustowska forest) and one microhabitat in the Czech Republic (Moravsky Kras). Ecological differentiation of Conocephalum conicum, Marchantia polymorpha and Pellia epiphylla populations is closely correlated with the soil chemistry. The evidence for this assumption are the significant positive correlations between concentrations of elements in soil and in the examined liverworts. In particular, correlations between contents of chromium and cobalt in soil and in Conocephalum conicum and between nickel, chromium, copper, and barium in soil and in Pellia epiphylla prove that these plants can be useful in monitoring of contamination of soil with elements mentioned above. Concentrations of cobalt in almost all the examined liverworts surpass the average background values of this element established for terrestrial bryophytes what proves that these plants tolerate increased accumulated amounts of this element and may therefore act as bioindicator for this heavy metal. Cationic equilibrium of Conocephalum conicum, Marchantia polymorpha and Pellia epiphylla examined according to Czarnowski (1977) pointed to the existence of some disturbances in ionic balance of these plants caused probably by elevated concentrations of microelements (especially iron, cobalt, lead, and copper) in their tissues.