Bioaccumulation of trace elements in lichens exposed to geothermal and volcanic activity from Copahue-Caviahue volcanic complex, Patagonia, Argentina

Abstract

The atmospheric pollution associated with the volcano Copahue activity was evaluated by analyzing the concentration of 33 elements including heavy metals in lichens. Fruticose thalli were collected between 7 and 18 km from the volcano crater, comprising a geothermal zone. Analytical data and geographic parameters were evaluated by Principal Component Analysis. Enrichment Factors was also calculated from elemental concentrations in the lichens. The Principal Components Analysis grouped the observations corresponding to the lichen samples in relation to the volcano crater distance, the thermal areas and the direction of the prevailing winds. Theless impacted area by volcanic products presented a lower concentration of toxic elements (S and Hg) and a higher concentration of biological elements (Ca, K, Mg and Mn) than the other areas. All studied sites showed S and Se enrichments, even in the most distant areas from the volcano crater. The S concentrations in lichen recorded in areas of volcanic activity were higher for the volcanic complexes: Copahue-Caviahue and Puyehue-Cordón-Caulle (2800-12000 μg/g) than those reported for the rest of the world (600-2800 μg/g).