The effect of air pollution on the integrity of chlorophyll, spectral reflectance response, and on concentrations of nickel, vanadium, and sulfur in the lichen Ramalina duriaei (De Not.) Bagl.

The following study was designed to determine the environmental impact of pollutants emitted by combustion of heavy fuel oil in Ashdod, in Southwestern Israel. For this purpose we measured concentrations of total S, V, and Ni in the local epiphytic fruticose lichen Ramalina duriaei, which grows in the peripheral region of the town, and compared these results with those obtained in thalli collected 100 km away, in the HaZorea Forest, northeastern Israel. We also transplanted thalli from the HaZorea Forest to the Ashdod region for a 10-month period. At the end of the experiment we measured the elemental content in all samples. In addition we measured chlorophyll degradation expressed as changes in the 435 nm/415 nm OD ratio, and changes in the spectral responses of the thalli. In several sites in the Ashdod region we found high concentrations of S, V, and Ni in transplanted thalli, which correlated with the NDVI values. These findings agree with other measurements of SO2 and V in the Ashdod area. We suggest that a high V/Ni ratio in lichens is a tracer for air pollution caused by the combustion of heavy fuel oil.