A Fourier transform-Raman spectroscopic study of lichen strategies on granite monuments

The biodeterioration of granite by Lecidea fuscoatra (L) Ach,, Porpidia cinereoatra (Ach,) Hertel & Knoph, and P. macrocarpa (DC.) Hertel & Schwab growing in the same environmental conditions has been studied by ruing Fourier transform-Raman spectroscopy Results were significantly different for the three species, with P. cinereoatra being the most active biodeteriorative lichen. This lichen was also the only one in which calcium oxalate and gypsum were identified spectroscopically. Physical disturbances to the substratum were evidenced in all lichens studied by the incorporation of material, such as quartz and feldspar; into their thalli, but this phenomenon varied considerably from species to species. The results indicate that lichen species can adopt different strategies and call have different biodeteriorative effects on granite, independently of environmental conditions and substrate.