Accumulation and localization of metals in lichen thallus under conditions of dust pollution during open mining of boxite deposits

Abstract

We studied the accumulation and localization of metals in the foliose lichens Lobaria pulmonaria, Hypogymnia physodes and Peltigera aphthosa, living in the impact zone of the Sredne-Timansky bauxite mine. A significant accumulation of Al (16–19 g/kg), Fe (16–20 g/kg) and Ti (0.3–0.7 g/kg) by thalli was revealed. From 29 to 82% of the total content of these metals is localized in dust particles weakly attached to the surface of the thalli. The total proportion of intra- and extracellularly bound Al, Fe and Ti did not exceed 11%. 15–56% of these metals were found in the residual fraction. An increase in the content of Cu, Pb, Co and Ni was detected in thalli collected in the impact area. It has been shown that the localization of metals in thalli depends both on the element under consideration and on the morphological and anatomical characteristics of the thalli: in L. pulmonaria, fine mineral particles were localized on the surface of the thalli; in the thalli of P. aphthosa, which do not have a lower cortex, mineral inclusions were found throughout the entire thickness of the thalli.