Elucidating the leaf-based heavy metal bioindication in two significant plant taxa from Caucasus

The present study was aimed at assessing the potential of two important plants of the Transcaucasia – Betula medwediewii Regel (Caucasian birch) and Veratrum album L. (white hellebore) - as bioindicators of pollution of the environment. Betula medwediewii is a subalpine and alpine deciduous tree species that is significant for soil and habitat development. Veratrum album is found in the high altitude regions, is also known to withstand extreme conditions and has been used in herbal medicine. Elemental analysis was conducted on the plant leaves for total heavy metals such as aluminium, cadmium, cobalt, lead, and zinc. Results of the study showed that, in the leaves of B. medwediewii, aluminium, cadmium, and zinc heavy metals were found to be within permissible levels but levels of cobalt and lead were above permissible levels. For V. album cadmium and zinc also remained within the normal range but aluminum, cobalt and lead levels were notably high. The results of the study indicate the distinct accumulation characteristics that these species possess a unique behaviour in the presence of heavy metal pollution in the Transcaucasian environment and both plants have a potential capability as bio indicators.