Moehringia trinervia (L.) Clairv. - a bioindicator of heavy metal pollution of the environment

Abstract

The concentrations of 5 heavy metals, Cd, Pb, Ni, Zn and Cu, were determined in Moehringia trinervia (L.) Clairv. collected from several sites in the Niepołomice Forest. This area is polluted by the numerous industrial plants of Krakow, mainly by the steel mill situated near the eastern city limits. The composite index obtained from the contents of the assayed elements was the basis for delineating 4 pollution zones of the forest: the western zone, which has the highest heavy metal pollution (closest to the steel mill), with a composite pollution index from 0.26 to 0.43; two moderate zones with indexes from 0.02 to O.15 and from -0.02 to -0.12 and the least polluted zone in the eastern area of the forest with an index of -0.18 to -0.29. It was found that Moehringia is an exceptionally good cadmium accumulator. The concentration of this element in the above-ground parts of this plant averaged about 9 µg g^-1.