Correlations between the concentration of adenosine tri phosphate, chlorophyll degradation and the amounts of airborne heavy metals and sulphur in a transplanted lichen

The lichen Ramalina duriaei (De Not.) Bagl. was transplanted to 12 biomonitoring sites during the period July1984-July 1985. The amounts of Ni, Cr, Cu, Zn, and Pb detected in the lichen thalli after the period of exposure, were compared with the ATP concentrations and the chlorophyll degradation in the same material. An inverse correlation between Pb, Cu, and ATP concentrations was found in the studied lichen. The degradation of chlorophyll a to phaeophytin a, as expressed by the ratio OD435/OD415 was inversely correlated with the amounts of Pb, Zn, Cu, and S in the lichen thallus. The amounts of the five heavy metals studied, were compared with those detected in R. duriaei transplanted to eight biomonitoring sites during the period 1979-1980. It is suggested that a regional increase in the amounts of Cr in the lichen exposed during the 1984/85 period is causally linked with emissions of Cr from the stacks of a new coal-fired power plant. The OD435/OD415 ratio was inversely correlated with the amounts of S in the lichen only in the material transplanted around the coal-fired power plant but not in the Tel Aviv area. No significant correlation was obtained between ATP and the amounts of S in the lichen.